Four checks catch most decay: speed on a real phone via PageSpeed Insights, every form submitted end to end, Search Console for errors and query trends, and a quick ask-the-assistants test to see whether AI still describes your business accurately.
Websites decay silently: a form breaks in a plugin update, a redirect loops, speed erodes one script at a time, and nobody notices until enquiries dry up. A quarterly half-hour catches almost all of it while it is still trivial.
The form check matters most and is skipped most. Submit every form yourself, from a phone, and confirm the notification arrives where a human reads it. Businesses lose whole months of leads to this one silent failure.
The four-step routine
PageSpeed Insights on your top three pages, mobile scores. Every form and click-to-call tested for real. Search Console: coverage errors, and which queries are growing or dying. Then ask two AI assistants what your business does and where, and correct whatever they get wrong at the source, your site and listings.
Calendar it. The businesses that do this boring loop simply do not have the emergencies the others do.