postmortem

The timeline is the easy part and the detection gap is the valuable part: not what broke, but how long it was broken before anyone knew and why. A worked example with its five sections, the distinction between the trigger and the cause, and the property that separates action items that ship from ones that do not.

Most postmortem processes fail in one of three predictable ways, and each has a mechanical fix rather than a cultural exhortation. The threshold that decides which incidents get one, the review that changes the document, the tracking that closes the items, and the measurement that says whether any of it is working.

A war story with no learning in it scores zero, however dramatic. The five beats of an incident narrative, the decision under uncertainty that is the actual subject of the question, and how to tell it when the incident was somebody else's fault.

Most postmortem documents are written, filed and never read again. The three parts that decide whether one changes anything, why action items without a named owner and a date are decoration, and the meeting rule that keeps blamelessness from becoming vagueness.