A well-run implementation ends with documentation, test evidence and a working environment. Eighteen months later that environment frequently bears only a partial resemblance to what was handed over — not through negligence, but through ordinary accumulated change.
Drift is normal and mostly invisible
A firewall rule added during an incident and never reviewed. A monitoring agent that stopped reporting after a rebuild. A certificate renewed manually by someone who has since left. None of these is dramatic; together they mean the documented design no longer describes the running system.
Monitoring only helps if someone reads it
Alert volume is the usual failure. A platform that produces hundreds of notifications a day trains its audience to ignore all of them. Correlating events into a small number of actionable alerts, each with a defined recipient and escalation, is worth more than broader coverage.
Review the architecture, not just the tickets
A periodic service review that covers capacity, risk and whether the architecture still fits what the business is doing will catch the structural problems that incident counts never surface.
In short
Assume drift, monitor for signal rather than volume, and review the design — not only the incidents.