What should you fix first?

An FMEAFailure Mode and Effects Analysis — a structured walk through the ways a system could fail, scoring each one so you tackle the worst first. lists the ways a system could fail, then rates each on three 1–10 scales. Their product — the Risk Priority NumberRisk Priority Number: Severity × Occurrence × Detection, from 1 to 1000. A ranking device, not a measurement — only meaningful next to the other rows. — sorts the list. The twist is detection: a middling failure no one would catch in time can outrank an obvious disaster.

RPN = Severity × Occurrence × Detection, each rated 1–10
Most urgent: TLS cert expires silently at RPN 224
1Act now
224RPN
2Plan a fix
162RPN
3Plan a fix
120RPN
4Plan a fix
120RPN
RPN bands (act / plan / monitor) are a working heuristic, not a standard — the score only ranks, it doesn't measure