No error. No warning. The site was “up”. It just wasn’t the site we thought we had.

How many caches are between you and your visitor?

On a typical managed WordPress site there are at least four, and they don’t talk to each other:

1. Browser cache on the visitor’s device. You can’t clear it. You can only tell it when things change.
2. CDN / edge cache (Cloudflare and friends). Caches images and scripts for sure; sometimes whole pages if someone turned on “cache everything”.
3. Server-level page cache — NGINX, LiteSpeed or Varnish in front of the web server. Invisible from inside WordPress. Often has no button you can see.
4. WordPress page cache — a plugin writing finished HTML to disk so PHP doesn’t run for every visitor.
5. Object cache — Redis or Memcached holding database results. This one caused a second, stranger bug on the same site: a plugin we activated stayed “active” in the admin while the cached list of active plugins told WordPress not to load it. Nothing ran until the cache was flushed.

Our stale homepage was layer 3. The WordPress cache plugin had already been cleared; the server in front of it hadn’t, and it kept serving a copy it had saved when the WordPress plugin was still running. The only fix was a button in the hosting control panel that no “Clear cache” link inside WordPress ever touched.

Why this is a business problem, not a technical one

Every “we changed the phone number on the website” that a customer later says they didn’t see. Every price update that didn’t take. Every “the site still shows the old promotion” conversation. Caching is the first thing to rule out, and almost nobody does, because it’s invisible unless you know to look at headers and timestamps.

How to check your own site in one minute

• Open your homepage in a private/incognito window and add ?x=1 to the end of the address. If the page with ?x=1 differs from the page without it, something upstream is serving a stale copy.
• View the page source (right-click → View Page Source) and search for the word “cache”. Many cache layers leave a dated comment at the top or bottom.
• Make a small, obvious edit — a word in the footer — and check it from your phone on mobile data five minutes later.

When we take a site onto Site Care the first job is a map of exactly which caches sit in front of it and how each one is cleared — then we clear all of them, in order, every time you ask for a change. Edits go live when you expect them to. That’s the whole job.