{"id":735249,"date":"2026-06-24T16:10:32","date_gmt":"2026-06-24T13:10:32","guid":{"rendered":"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/"},"modified":"2026-06-24T16:10:32","modified_gmt":"2026-06-24T13:10:32","slug":"why-some-channels-reward-breadth-and-others-require-commitment","status":"publish","type":"post","link":"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/","title":{"rendered":"Why some channels reward breadth and others require commitment"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_85 counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-6a3cc5fdca09d\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #dd3333;color:#dd3333\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #dd3333;color:#dd3333\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-6a3cc5fdca09d\" checked aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#Small-budget_tests_can_mislead_you_Learn_how_response_curves_affect_channel_evaluation_budget_allocation_and_growth_decisions\" >Small-budget tests can mislead you. Learn how response curves affect channel evaluation, budget allocation, and growth decisions.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#The_two_shapes_%E2%80%94_and_the_only_part_that_matters\" >The two shapes \u2014 and the only part that matters<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#How_this_looks_in_a_marketing_campaign\" >How this looks in a marketing campaign<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#The_allocation_logic_restated\" >The allocation logic, restated<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#C-shaped_channels_go_wide\" >C-shaped channels, go wide<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#S-shaped_channels_go_deep_or_skip\" >S-shaped channels, go deep or skip<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#Which_channels_are_which\" >Which channels are which?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#When_to_go_wide_and_when_to_go_deep\" >When to go wide and when to go deep<\/a><ul class='ez-toc-list-level-5' ><li class='ez-toc-heading-level-5'><ul class='ez-toc-list-level-5' ><li class='ez-toc-heading-level-5'><ul class='ez-toc-list-level-5' ><li class='ez-toc-heading-level-5'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/buradabiliyorum.com\/en\/why-some-channels-reward-breadth-and-others-require-commitment\/#Topics_on_this_page\" >Topics on this page<\/a><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2 class=\"subhead\" itemprop=\"alternativeHeadline\"><span class=\"ez-toc-section\" id=\"Small-budget_tests_can_mislead_you_Learn_how_response_curves_affect_channel_evaluation_budget_allocation_and_growth_decisions\"><\/span>Small-budget tests can mislead you. Learn how response curves affect channel evaluation, budget allocation, and growth decisions.<br \/>\n<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><\/p>\n<div class=\"bialty-container\">\n<p>Many budget allocation strategies assume that every channel follows the same pattern: the first dollar is the most productive, and each additional dollar yields a slightly lower return.<\/p>\n<p>The charts below show what that pattern looks like.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img fetchpriority=\"high\" decoding=\"async\" width=\"2048\" height=\"778\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-188.png\" alt=\"Image 188\" class=\"wp-image-480766\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-188.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-188-768x292.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-188-1536x584.png 1536w\" sizes=\"(max-width: 2048px) 100vw, 2048px\"><\/figure>\n<\/div>\n<p>The log shape means that the first dollar is the most productive, and each subsequent dollar is worth a little less. When every channel looks like that, the <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/game\/\" data-internallinksmanager029f6b8e52c=\"7\" title=\"Game\" target=\"_blank\" rel=\"noopener\">game<\/a> plan is to spread the budget to as many channels as possible and equalize the marginal CPAs to maximize profit.<\/p>\n<p>But not every channel looks like that. Some have a warm-up region where the early spend is the least efficient, not the most. On those channels, the logic above breaks, and so does the \u201ctest small, scale the winners\u201d playbook that most of the industry runs on autopilot.\u00a0<\/p>\n<p>The difference comes down to one question about the channel: Is the response curve C-shaped or S-shaped?<\/p>\n<p>The answer can change how you <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/download-scripts-themes-apps\/\" data-internallinksmanager029f6b8e52c=\"9\" title=\"Download Scripts &amp; Themes &amp; Apps\" target=\"_blank\" rel=\"noopener\">app<\/a>roach channel testing and channel measurement, including any MMM analysis. Moreover, Google has been incorporating more S-shaped campaign types, and after its Google Marketing Live announcements, this trend seems set to continue.<\/p>\n<h2 id=\"the-two-shapes-and-the-only-part-that-matters\" class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"The_two_shapes_%E2%80%94_and_the_only_part_that_matters\"><\/span>The two shapes \u2014 and the only part that matters<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The response curve plots output (conversions, revenue) against input (spend). This <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/general\/\" data-internallinksmanager029f6b8e52c=\"3\" title=\"General\" target=\"_blank\" rel=\"noopener\">general<\/a>ly results in two types of curves in marketing.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"965\" http: alt=\"Image 189\" class=\"wp-image-480767\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189-768x362.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189-1536x724.png 1536w\" data-lazy-sizes=\"(max-width: 2048px) 100vw, 2048px\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189.png\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"965\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189.png\" alt=\"Image 189\" class=\"wp-image-480767\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189-768x362.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-189-1536x724.png 1536w\" sizes=\"auto, (max-width: 2048px) 100vw, 2048px\"><\/figure>\n<\/div>\n<ul class=\"wp-block-list\">\n<li><strong>C-shaped (concave):<\/strong> Diminishing returns from the very first dollar. A log or power curve. Picture the top-left quarter of a circle: steep at the start, flattening as you go.<\/li>\n<li><strong>S-shaped (sigmoid):<\/strong> A slow, inefficient start, then an inflection point where it gets steep, followed by a flattening into saturation. A logistic curve.<\/li>\n<\/ul>\n<p>The response curve itself isn\u2019t what you allocate against. You allocate against the marginal curve, the derivative, which answers the question: \u201cWhat did the next dollar buy me?\u201d That\u2019s where the shapes diverge in a way that matters.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1044\" http: alt=\"Image 192\" class=\"wp-image-480770\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192-768x392.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192-1536x783.png 1536w\" data-lazy-sizes=\"(max-width: 2048px) 100vw, 2048px\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192.png\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1044\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192.png\" alt=\"Image 192\" class=\"wp-image-480770\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192-768x392.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-192-1536x783.png 1536w\" sizes=\"auto, (max-width: 2048px) 100vw, 2048px\"><\/figure>\n<\/div>\n<ul class=\"wp-block-list\">\n<li>For a C-curve, marginal return is highest at the first dollar and falls in only one direction. Marginal CPA rises from the first dollar onward. If conversions are a*ln(s), marginal conversions per dollar are a\/s, so marginal CPA is s\/a, climbing in a straight line as you scale. There\u2019s no warm-up. The cheapest conversion you\u2019ll ever buy is the first one.<\/li>\n<li>For an S-curve, marginal return starts low, rises to a peak at the inflection point, then falls. Marginal CPA is U-shaped. It\u2019s expensive at the start, bottoms out around the inflection point, then climbs into saturation.<\/li>\n<\/ul>\n<p>That region of increasing marginal returns is the whole story. It\u2019s the difference between a channel where small budgets are productive and one where they are wasted.<\/p>\n<div style=\"background: radial-gradient(circle at 30% 40%, rgba(184, 111, 255, 0.15), rgba(0, 169, 255, 0.15) 40%, #CDE8FD 70%); padding: 30px; width: 100%; max-width: 802px; color: #000000 !important; font-family: Arial, sans-serif; margin: 25px 0 30px 0; border-radius: 8px; box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1); position: relative; box-sizing: border-box;\">\n<div style=\"width: 100%; max-width: 100%; margin-bottom: 20px; text-align: left; padding-right: 20px; box-sizing: border-box;\">\n<div id=\"semrush-one-headline\" class=\"headline-responsive\" style=\"font-family: Oswald, sans-serif; font-size: 30px; font-weight: normal; margin: 0; color: #000000 !important; line-height: 1.2;\">\n        See exactly how <span style=\"background: linear-gradient(90deg, #D56EFE 0%, #068EF8 51%); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;\">your competitors win<\/span>.\n      <\/div>\n<p id=\"semrush-one-subhead\" style=\"font-family: Roboto, sans-serif; font-size: 18px; font-weight: 300; line-height: 25px; margin: 12px 0 0 0; color: #000000 !important;\">\n        Uncover the keywords, ads, landing pages, and strategies driving your competitors\u2019 paid search success\u2014and find your next opportunity to outperform them.\n      <\/p>\n<\/p><\/div>\n<div style=\"margin-bottom: 15px;\">\n      <span id=\"semrush-one-cta\" style=\"display: inline-block; background-color: #FF642D; color: white; height: 44px; border: none; border-radius: 5px; cursor: pointer; font-size: 16px; padding: 0 24px; font-weight: bold; white-space: nowrap; box-sizing: border-box; text-decoration: none; line-height: 44px;\">Analyze your competitors<\/span>\n    <\/div>\n<\/p><\/div>\n<style>\n  @media (max-width: 768px) {\n    .headline-responsive {\n      font-size: 30px !important;\n      line-height: 1.3 !important;\n    }\n  }\n<\/style>\n<h2 id=\"how-this-looks-in-a-marketing-campaign\" class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"How_this_looks_in_a_marketing_campaign\"><\/span>How this looks in a marketing campaign<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Say your CPA goal is $50. Here is an S-shaped channel, modeled as Conversions = 1000 \/ (1 + e^(-0.25(s \u2013 20))), with spend in the thousands and the inflection at $20,000\/month:<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2000\" height=\"1520\" http: alt=\"Image 191\" class=\"wp-image-480769\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191.png 2000w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191-768x584.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191-1536x1167.png 1536w\" data-lazy-sizes=\"(max-width: 2000px) 100vw, 2000px\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191.png\"><img loading=\"lazy\" decoding=\"async\" width=\"2000\" height=\"1520\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191.png\" alt=\"Image 191\" class=\"wp-image-480769\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191.png 2000w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191-768x584.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-191-1536x1167.png 1536w\" sizes=\"auto, (max-width: 2000px) 100vw, 2000px\"><\/figure>\n<\/div>\n<p>Run the $10,000 test that a sane person runs before committing real budget. Average CPA comes back at $132, marginal around $94. If those two metrics are all you look at, you conclude that this channel can\u2019t hit $50, so let\u2019s kill it.<\/p>\n<p>That verdict is wrong. At $20,000 to $25,000, the channel is running at an average of $32 to $40, and the marginal dollar in the $15,000 to $25,000 band costs $18. That\u2019s not \u201cbarely viable.\u201d In that band, it\u2019s the best marginal buy you have. The small test fell within the warm-up and reversed the conclusion.<\/p>\n<p>In a C-shaped channel, the small test would have shown you the best the channel can do. On an S-shaped channel, it shows you the worst.<\/p>\n<p>This is the trap. The standard playbook is \u201ctest small, scale what works.\u201d On S-curves, small tests systematically condemn channels that would\u2019ve worked at scale because the test is structurally stuck in the inefficient region.<\/p>\n<p><!-- START INLINE FORM --><\/p>\n<p><!-- END INLINE FORM --><\/p>\n<hr class=\"wp-block-separator has-text-color has-cyan-bluish-gray-color has-css-opacity has-cyan-bluish-gray-background-color has-background\">\n<h2 id=\"the-allocation-logic-restated\" class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"The_allocation_logic_restated\"><\/span>The allocation logic, restated<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3 class=\"wp-block-heading\" id=\"h-c-shaped-channels-go-wide\"><span class=\"ez-toc-section\" id=\"C-shaped_channels_go_wide\"><\/span>C-shaped channels, go wide<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The optimization is convex. There\u2019s one global optimum, the equimarginal rule from the marginal-CPA post applies cleanly, and the solution is usually interior, meaning lots of channels get funded.<\/p>\n<p>Even a small allocation is productive because the first dollar is the best dollar. Run many channels lean, reallocate continuously at the margin, and pull back the instant marginal CPA crosses your goal.<\/p>\n<h3 class=\"wp-block-heading\" id=\"h-s-shaped-channels-go-deep-or-skip\"><span class=\"ez-toc-section\" id=\"S-shaped_channels_go_deep_or_skip\"><\/span>S-shaped channels, go deep or skip<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The optimization is non-convex. A small allocation can be strictly worse than zero because below the inflection your marginal return sits under your target, and you\u2019ve sunk money to get nowhere. <\/p>\n<p>The decision isn\u2019t \u201chow much.\u201d It is binary: commit past the threshold, or don\u2019t fund it at all. There\u2019s a real minimum viable budget, and it\u2019s often above normal test budgets. You can\u2019t sprinkle an S-curve and expect efficiency, and you can\u2019t evaluate one on an underfunded test.<\/p>\n<p>Those two rules can look like they fight each other, but that\u2019s only true to a certain point. Past the inflection, an S-curve is concave, so the equimarginal rule governs it exactly as it governs a true C. The S-specific instruction \u2014 commit a block instead of sprinkling \u2014 is only about the <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/trip-and-travel\/\" data-internallinksmanager029f6b8e52c=\"10\" title=\"Trip &amp; Travel\" target=\"_blank\" rel=\"noopener\">trip<\/a> from zero to past the inflection.<\/p>\n<p>Shape is therefore mostly a launch-and-evaluation problem. Getting a new prospecting channel into its efficient range requires a committed block and patience with ugly early numbers. Once it clears the inflection, you manage it at the margin like everything else, right up until you consider cutting it hard, where shape matters again because the downside is a cliff, not a ramp.<\/p>\n<p>This is the part that\u2019s genuinely counterintuitive, and it echoes the original marginal-return point: The right move isn\u2019t always the one that looks most efficient at a small scale.<\/p>\n<h2 id=\"which-channels-are-which\" class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"Which_channels_are_which\"><\/span>Which channels are which?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The historical default was concave. Simon and Arndt reviewed more than 100 studies and concluded that advertising follows the law of diminishing returns, a concave response.\u00a0<\/p>\n<p>The dissent came later: Vakratsas, Feinberg, Bass, and Kalyanaram found that threshold effects do exist and that response is not necessarily globally concave. Their explanation for why thresholds were so hard to find is the useful part. Mature accounts already operate inside the effective range, so the warm-up never shows up in the data, and most studies fit a concave model (the double-log) that can\u2019t reject an S-curve even when one is present.<\/p>\n<p>The platform shift has made the threshold visible again. Here is a fuller map, ordered roughly from C to S. The shape column is an inference from how each system targets and learns, not a measured constant, and the right shape for your account still has to be measured.<\/p>\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1142\" http: alt=\"Image 190\" class=\"wp-image-480768\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190-768x428.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190-1536x857.png 1536w\" data-lazy-sizes=\"(max-width: 2048px) 100vw, 2048px\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190.png\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1142\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190.png\" alt=\"Image 190\" class=\"wp-image-480768\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190-768x428.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-190-1536x857.png 1536w\" sizes=\"auto, (max-width: 2048px) 100vw, 2048px\"><\/figure>\n<p>Two rows do most of the work.<\/p>\n<p>AI Max is the live example of a channel migrating from C toward S. Swapping explicit keywords for broad and keywordless matching means it needs conversion volume to learn which queries convert, so below a data threshold, it explores badly. <\/p>\n<p>The mixed independent results fit that: Google reports about 14% more conversions on average and up to 27% for exact-match-heavy campaigns, while independent testing reports 84% of advertisers seeing neutral or negative results. Much of that spread is accounts that turned it on without the conversion volume to clear the learning region.<\/p>\n<p>Performance Max is the trap, because its curve is a composite. It blends a harvesting layer (branded, retargeting, Shopping against existing intent) with a prospecting layer (keywordless expansion across surfaces). The harvesting layer is a cheap C that pays off on the first dollar. The prospecting layer is the S underneath. <\/p>\n<p>Blended, the early efficiency looks great, because you are mostly skimming demand you already had, and the average hides the prospecting warm-up entirely. That is also why the platform is glad to optimize it for you: the blend flatters the headline number. You can\u2019t read PMax or run the shape analysis on it until you split the harvesting from the prospecting.<\/p>\n<p>The throughline runs in two layers. Rules-based auctions capture the best inventory first, which yields concavity; machine-learning systems must be fed before they are efficient, which introduces a threshold. Underneath both, harvesting existing demand is concave and mostly non-incremental, while creating new demand is the S-shaped part where the real growth and the real warm-up cost both sit.<\/p>\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1645\" http: alt=\"Image 193\" class=\"wp-image-480771\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193-768x617.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193-1536x1234.png 1536w\" data-lazy-sizes=\"(max-width: 2048px) 100vw, 2048px\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193.png\"><img loading=\"lazy\" decoding=\"async\" width=\"2048\" height=\"1645\" src=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193.png\" alt=\"Image 193\" class=\"wp-image-480771\" srcset=\"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193.png 2048w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193-768x617.png 768w, https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/image-193-1536x1234.png 1536w\" sizes=\"auto, (max-width: 2048px) 100vw, 2048px\"><\/figure>\n<\/div>\n<p>Average versus marginal: total over spend, or the slope where you stand.<\/p>\n<p>What you allocate against is marginal incremental return, the slope of the incremental curve at your operating point. A holdout fixes the first axis only. Time-sliced marginal CPA on attributed data fixes the second only. A multi-cell scaling test gets both, at a cost.\u00a0<\/p>\n<p>MMM (method 1) estimates the whole curve from aggregate data and sidesteps click attribution entirely, but pays in identifiability and modeling assumptions instead. Most arguments about \u2018what is working\u2019 are two people standing on different axes.<\/p>\n<p>There are two major cautions, and I would flag both as genuinely unsettled rather than settled facts.\u00a0<\/p>\n<ul class=\"wp-block-list\">\n<li>Separating a true S-curve from \u201cconcave with a high half-saturation point\u201d is hard, because a concave model will fit S-shaped data well enough to hide the inflection (this is the Vakratsas point, and it applies to your own dashboards as much as to academic studies).\u00a0<\/li>\n<li>The learning phase may be a one-time fixed cost to train the model rather than a permanent feature of the steady-state curve. If it is transient, the channel may behave concavely at the margin once it is trained, and the S you measured was a startup artifact. The truth is probably a mix: a one-time training cost, plus an ongoing minimum-volume requirement to stay efficient. Treat every shape call as provisional and re-check it.<\/li>\n<\/ul>\n<p>One more failure mode, and this one is not unsettled <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/sciencee\/\" data-internallinksmanager029f6b8e52c=\"5\" title=\"Science\" target=\"_blank\" rel=\"noopener\">science<\/a> but a matter of where you are standing on the curve. An S only looks like an S if your data spans the inflection.\u00a0<\/p>\n<p>Above the inflection, an S is concave, mathematically identical to a C. Look at only the $20,000-and-up rows of the table above: marginal CPA rises monotonically from $18, a textbook C-curve, and the convex warm-up is invisible because you are no longer operating in it.\u00a0<\/p>\n<p>Established accounts usually sit past the inflection, which is exactly why Vakratsas found thresholds so hard to detect, and why you can run an S-shaped channel for years, correctly, while believing it is concave. The tell arrives the day you cut hard and fall off the inflection instead of easing down a slope.<\/p>\n<h2 id=\"when-to-go-wide-and-when-to-go-deep\" class=\"wp-block-heading\"><span class=\"ez-toc-section\" id=\"When_to_go_wide_and_when_to_go_deep\"><\/span>When to go wide and when to go deep<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The marginal-return post told you to equalize marginal CPAs across the program. That rule is still correct, but the shape of the curve tells you how you\u2019re allowed to get there.\u00a0<\/p>\n<ul class=\"wp-block-list\">\n<li>On C-shaped channels, you can get there by sprinkling, because every dollar is productive and breadth is the natural answer.\u00a0<\/li>\n<li>On S-shaped channels, you have to commit a block of budget past the inflection before the channel earns its place, and then concentrate rather than spread.<\/li>\n<\/ul>\n<p>Lay the harvest-versus-create cut on top. Harvesting channels (branded, retargeting, non-brand search) are your C-curves: fund the first dollars, then cap them early, because they saturate fast and most of the tail isn\u2019t incremental, no matter how strong the attributed ROAS looks.\u00a0<\/p>\n<p>Prospecting channels (Meta, <a href=\"https:\/\/buradabiliyorum.com\/en\/category\/social-mediaa\/\" data-internallinksmanager029f6b8e52c=\"1\" title=\"Social Media\" target=\"_blank\" rel=\"noopener\">YouTube<\/a>, LinkedIn, the expansion half of PMax) are your S-curves and your only real source of incremental growth: commit past the warm-up or don\u2019t start, and judge them on incremental lift rather than attributed CPA, or you\u2019ll kill the thing that was working.<\/p>\n<p>Classic search rewards going wide. PMax, AI Max, and Meta prospecting reward going deep on fewer bets and giving each enough volume to clear the warm-up. Run an S-curve like a C-curve and you\u2019ll starve it, read the underfunded result, and kill a channel that would\u2019ve been one of your best.<\/p>\n<div class=\"ttd-topics-display\">\n<div class=\"ttd-topics-content\">\n<h5><span class=\"ez-toc-section\" id=\"Topics_on_this_page\"><\/span>Topics on this page<span class=\"ez-toc-section-end\"><\/span><\/h5>\n<div class=\"ttd-topics-links\">Marketing mix modelingAdvertising campaignGoogleReturn on investmentCustomer acquisition costLinkedInMetaSearch Engine LandYouTube<\/div>\n<\/div>\n<div class=\"ttd-topics-show-extra-button\">+5 more<\/div>\n<\/div>\n<\/div>\n<blockquote><p><strong><span style=\"color: #ff6600;\">If you liked the article, do not forget to share it with your friends. Follow us on\u00a0<span style=\"color: #ff0000;\"><a style=\"color: #ff0000;\" href=\"https:\/\/news.google.com\/publications\/CAAqBwgKMN63nwsw68G3Aw\" target=\"_blank\" rel=\"nofollow noopener noreferrer\">Google News<\/a><\/span>\u00a0too, click on the star and choose us from your favorites.<\/span><\/strong><\/p><\/blockquote>\n<blockquote>\n<p style=\"text-align: center;\"><strong>If you want to read more like this article, you can visit our <span style=\"color: #ff9900;\"><a style=\"color: #ff9900;\" href=\"https:\/\/buradabiliyorum.com\/en\/category\/technology\/\" target=\"_blank\" >Technology<\/a><\/span> category.<\/strong><\/p>\n<\/blockquote>\n<p><span style=\"color: black;\"><a style=\"color: #ff9900;\" href=\"https:\/\/searchengineland.com\/channels-breadth-commitment-480765\" target=\"_blank\" >Source<\/a><\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Small-budget tests can mislead you. Learn how response curves affect channel evaluation, budget allocation, and growth decisions. Many budget allocation strategies assume that every channel follows the same pattern: the first dollar is the most productive, and each additional dollar yields a slightly lower return. The charts below show what that pattern looks like. The&#8230;<\/p>\n","protected":false},"author":1,"featured_media":735250,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"fifu_image_url":"https:\/\/searchengineland.com\/wp-content\/seloads\/2026\/06\/Why-some-channels-reward-breadth-and-others-require-commitment.png","fifu_image_alt":"","footnotes":""},"categories":[18],"tags":[],"class_list":["post-735249","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-technology"],"_links":{"self":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/735249","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/comments?post=735249"}],"version-history":[{"count":0,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/posts\/735249\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/media\/735250"}],"wp:attachment":[{"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/media?parent=735249"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/categories?post=735249"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/buradabiliyorum.com\/en\/wp-json\/wp\/v2\/tags?post=735249"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}