“Clear browser data” combines items that solve different problems. The cache stores copies of images, scripts and styles for speed. Cookies store site state such as a session, preference or identifier.
Clear cache when
A page keeps showing an old design, a script behaves differently from other devices or corrupted local files are suspected. A hard refresh may be enough before deleting everything.
Clear cookies when
A site is stuck in a login loop, an account switch fails or you want to reset that site's stored session. Clearing all cookies signs you out broadly, so start with the affected domain.
Privacy implications
Removing cookies reduces stored identifiers but does not erase server records, account activity or fingerprints. Cached files are primarily a performance concern.
Use targeted controls
Modern browsers let users remove data for one site. That preserves unrelated sessions and makes troubleshooting easier because only one variable changes.
Service workers are another layer
Progressive web apps may cache resources through a service worker. Clearing ordinary cached files may not reset that application state; use the browser's site-data controls and inspect the registered worker.
Site owners should fix delivery
Do not train every visitor to clear their browser after each release. Use versioned asset filenames, correct Cache-Control headers and targeted CDN invalidation. Inspect Age, ETag, Last-Modified and service-worker behavior from a clean session.
Record which action resolved the issue. If clearing cookies fixes it, investigate session creation and expiry. If disabling cache fixes it, correct the deployment or cache policy. The troubleshooting step should lead to an engineering fix, not become permanent user documentation.