Accessibility + Core Web Vitals: the overlooked UX wins

Core Web Vitals (LCP, INP, CLS) tend to get treated as "performance metrics". Accessibility tends to get treated as "compliance work". That split is convenient, and it's wrong in practice. A keyboard user doesn't experience your site as a Lighthouse report. They experience it as a sequence of interactions: tab, focus, type, submit, wait, recover, continue. The same bottlenecks that hurt your Web Vitals routinely break assistive-tech UX. The nice part is that the fixes often pull double duty. INP is the clearest example. Google promoted Interaction to Next Paint as the responsiveness metric in Core Web Vitals (replacing FID) because it reflects real interaction latency across the session, not just the first tap. If INP is bad, keyboard navigation is usually miserable: focus moves late, keypresses queue up, menus open after you've already moved on. Anyone who has watched an accordion open and immediately close because the browser finally "caught up" has seen a real-world INP problem, not