Fast on a mid-range phone, not just your laptop
Most visitors will meet your site on a mid-range Android over an average connection. That is the device we optimise for, because it is the one that decides whether people wait.
In practice: server-rendered HTML rather than a blank page that fills in later, images sized and served in modern formats, fonts loaded without blocking, and JavaScript kept to what genuinely needs to run in the browser. We measure Core Web Vitals - LCP, INP and CLS - before launch and after.