“My uptime monitor says everything's fine — so why are customers seeing errors?”
If you've ever gotten a “your site is down” message from a customer while your uptime dashboard showed a calm green 100%, you've hit the core limitation of external monitoring.
An external monitor requests one URL and checks the response. That's it. It can't see anything WordPress knows about itself — so it misses the failure modes that actually take WordPress sites down.
1. The cached homepage lies
A full-page cache can keep serving a 200 OK for the front page while checkout, login, or the REST API throw fatals. The pinger is happy; your conversion rate is not.
2. WP-Cron is a silent single point of failure
When it stalls, backups stop, order-confirmation emails stop, scheduled content stops — with zero change to the homepage's HTTP response.
3. “Up” is not “healthy”
A site can respond in 200ms and still be running a known-vulnerable plugin, an outdated PHP version, or throwing recoverable fatals on every request.
The fix: monitor from inside
A small plugin running in WordPress can report what an outside request never sees — the last fatal error (with file and line), the last successful cron tick, live database and REST checks, and the full plugin/theme inventory with available updates. That's the layer external tools structurally cannot reach.
See also: Zubbin vs. an external-only monitor
See it on your own site
The plugin is free on WordPress.org — your first health snapshot arrives in minutes.
Free forever plan · No credit card required