Section 1
Why these five case studies are worth your attention
Marketing case studies usually deserve skepticism: self-reported, survivorship-biased, vague about method. The web.dev archive is the closest thing the industry has to the opposite. Vodafone's result comes from a controlled A/B test, the same landing page, with one version optimized to render its main content 31% faster. Renault's comes from four months of field data across 10 million visits in 33 countries, collected with its analytics partner. Rakuten 24 instrumented real users with the web-vitals library and correlated performance against revenue. The method is the point. These are companies publishing their measurement setup alongside their numbers, which is what allows an outsider to learn from them honestly. For service-business operators, they answer a question taste never can: when a website changes, what actually moves, and by how much. The answers cluster around one variable with striking consistency: how fast the page becomes usable. To see how this connects to the wider system, read [Case Study: How Category-Leading Brands Built a Movement with Storytelling](/blog/case-study-how-built-a-movement-with-storytelling).
Section 2
Five documented results, decoded
The table below summarizes what each company changed, what it measured, and what a service business should take from it. Read the results column carefully: these are not small effects. Agrofy cut load abandonment from 3.8% to 0.9%, a 76% reduction in people who gave up before seeing anything. The Economic Times cut bounce 43% across its whole origin. None of these wins involved a new brand identity, new messaging, or new photography. They involved server-side rendering, image optimization, removing render-blocking code, and disciplined measurement. For a service business, the translation is direct: before commissioning a visual redesign, establish whether your current site is simply too slow to convert, because that fix is cheaper, faster, and the only one with documented effect sizes this large.
Section 3
The honest caveats before you extrapolate
Decoding these studies honestly means naming their limits. First, several results are correlations from field data rather than controlled experiments, Renault and Rakuten found strong relationships between speed and outcomes, but only Vodafone's A/B test isolates causation cleanly. Second, these are large consumer businesses with enormous traffic; a twenty-person consultancy will not measure a 13% conversion swing with statistical confidence in a month. Third, every site started from a measurably slow baseline, if your pages already load fast, further speed work yields diminishing returns. What transfers regardless of scale is the mechanism: buyers on mobile connections abandon pages that make them wait, and lead forms convert worse when the page stutters. What also transfers is the practice, measure before and after. The companies in this archive earned the right to claim results because they instrumented first. Most service businesses redesign without ever recording a baseline, which guarantees the new site can never prove anything. For a deeper look at this, see [How to Express Your Positioning Through Web Design (Without Saying a Word)](/blog/expressing-positioning-through-web-design).
Section 4
Run your own documented redesign
The replicable lesson is not any single number, it is the operating discipline. Before touching design: record your baseline. PageSpeed Insights and Chrome's user-experience data show your Core Web Vitals; your analytics show bounce, time to lead, and form completion by page. Then fix the documented offenders in order: oversized images, render-blocking scripts, slow server response. Then re-measure on the same instruments and keep the before-and-after. This is precisely how ConvertOS, the web-design module of LeverageOS, treats a rebuild, as an experiment with a baseline, not a beauty contest, because a service business that documents its own redesign earns proof it can publish, the same way these companies did. To be clear, the results in this article belong to Vodafone, Renault, Rakuten, Agrofy, and The Economic Times as documented on web.dev, and the method belongs to anyone willing to measure. A strategy call can scope what your baseline says first. A useful companion to this piece is [Case Studies: When AI Automation Went Wrong](/blog/case-studies-when-ai-automation-went-wrong).