LCP, CLS, INP — what actually moves revenue vs. what's vanity.
Vitals scores are a proxy. Revenue is the target. Most teams chase a green Lighthouse badge and miss the two or three fixes that actually shift checkout completion.
Fix 1: preload the LCP image, don't lazy-load it. Fix 2: reserve space for above-the-fold media to kill CLS. Fix 3: defer non-critical JS until interaction.
Fix 4: replace third-party widgets that block INP with server-rendered alternatives. Fix 5: ship a smaller font subset and self-host it.
Measure with field data (CrUX, RUM), not just lab runs. Lab metrics lie about real-user devices on real networks.