Speed is a ranking factor, a conversion factor and a margin factor
Google's threshold is unforgiving, but the user math is worse: a one-second delay cuts conversions by 7% and satisfaction proportionally. Performance is not a technical detail - it is a growth channel, and it is the only one where the fixes are permanent.
The audit that finds the leaks
Run Lighthouse on mobile and desktop, then read past the score: Largest Contentful Paint (target under 2.5s - usually an image or hero problem), First Input Delay / Interaction to Next Paint (target under 200ms - usually third-party scripts), Cumulative Layout Shift (target under 0.1 - usually images without dimensions or injected widgets), and Total Blocking Time (usually analytics and chat widgets).
- Images: modern formats, responsive sizes, lazy-load below the fold
- Fonts: subset, preload, avoid layout-shifting swaps
- Scripts: defer third-party tags, consolidate, self-host critical ones
- Rendering: avoid client-side-only above-the-fold content
The performance discipline
Performance decays - every script added, every image uploaded without a spec, every plugin installed. The discipline: a performance budget (site ships under 200KB critical JS, LCP under 2.5s), a monthly Lighthouse run, and a rule that no feature ships that drops the budget. Sites we manage hold 90+ scores by policy, not luck.
