Website speed affects revenue because visitors leave slow pages before they see your offer, and because search engines use page experience as a ranking signal. The usual causes are oversized images, render-blocking scripts and third-party embeds, all of which can be fixed without a full rebuild.
Speed isn't a technical vanity metric. It is tied to bounce rate, conversion rate and search visibility. Users decide whether to stay within the first few seconds.
The most common culprits are unoptimised images, render-blocking scripts, and third-party embeds that were added once and never audited again.
Modern frameworks help through image optimisation and code splitting, but architecture choices only get you halfway. Content and scripts added later are where most sites slow down.
A quarterly performance audit that checks Core Web Vitals, image weight and third-party scripts catches regressions before they cost you conversions.
Treat site speed as an ongoing discipline, not a one-time launch checklist item.