Nothing, at first. That is the problem. A neglected website rarely fails with a warning. It degrades quietly for months and then breaks at an inconvenient moment, usually when nobody is watching.
This is the order in which things usually go wrong on the sites that come to us after a year without care:
Updates stack up
Plugin, theme and core updates go unapplied. Nothing looks different yet, but each missed release widens the gap between your site and the versions that are still supported and patched.
Something breaks silently
A plugin conflict or an expired licence takes down a contact form or a checkout step. Enquiries stop and nobody notices, because a form that fails quietly looks exactly like a quiet week.
A known vulnerability is used
An unpatched plugin with a published vulnerability gets exploited. Patchstack’s annual research found 96% of new WordPress vulnerabilities in plugins rather than core, which is why plugin updates matter more than any other single task. Now you are paying for a malware clean-up instead of maintenance.
Each stage is cheaper to prevent than to repair. That is the whole argument for a maintenance plan, and it is why the plans below are priced as a monthly routine rather than an emergency call-out.