CRO

CRO became a discipline in its own right in the late 2000s, when tools like Optimizely and VWO made A/B testing accessible. The underlying idea is simple: lifting conversion on the traffic you already have is mathematically equivalent to lowering acquisition cost. As traffic gets more expensive, that makes CRO one of the highest-ROI lines on a marketing slate. Moving CVR from 1.5% to 2.0% on the same 1M visits raises revenue 33% with zero extra spend.

A typical CRO loop runs in five steps: diagnose quantitatively in GA4 or Mixpanel, diagnose qualitatively with heatmaps and session replays in Hotjar or Microsoft Clarity, form a sharp hypothesis ('mobile users abandon the credit card field because it's too long'), validate with an A/B test, and only ship statistically significant winners. Korean teams typically use Hackle, Whatap or GA4 in place of the Western tools, but the loop is identical.

The classic CRO failure mode is staying in the realm of button-colour tests. The lifts that actually move the business almost always come from substantive changes. When Toss collapsed money transfer from a three-step flow into a single 'enter recipient and send' interaction, conversion exploded — and the win was about cognitive friction, not visual polish. Copy, pricing presentation, form-field count and page structure are where the real CRO work lives.

AI search has pushed the CRO surface area outside your own site. When users meet your brand inside a ChatGPT answer first, that answer effectively becomes your true landing page. If the AI summarises your pricing or features incorrectly, expectations are mis-set before the user ever clicks, and on-site CVR drops as a result. A portion of GEO work is now functionally CRO work, which means audits of how your content is being summarised need to be a recurring task.

If you want to push CRO further, look at CVR distribution rather than CVR average. Split mobile versus desktop, new versus returning, KR versus US versus JP. Averages routinely hide enormous leaks — mobile checkout, guest purchase flows, foreign-currency payment paths — and fixing one or two of those segment-level leaks usually moves blended CVR more than dozens of generic page tests combined.