Run a Post-Mortem on That Job or Move On (Decision Tree)

Why this matters

Most jobs do not need a post-mortem. They went fine, or the hiccup was trivial, and dragging the crew through a review of every ordinary day is how you teach them that reviews are a waste of time. But some jobs are packed with a lesson that will save you the next ten, and letting those slide by unexamined is how a shop repeats the same expensive mistake for years. A post-mortem, also called an after-action review, is a short structured look back at a finished job to pull out what to keep and what to change. The skill here is not running one. It is knowing which jobs earn one.

Safety first: a real safety event is an automatic yes

Before any triage, one rule overrides everything. If someone was hurt or nearly hurt, if there was a fire, a shock, a fall, a gas event, or a near-miss with real injury potential, the review is mandatory, full stop, and the immediate hazard should already be controlled before you are reading this. You do not weigh the cost of a review against a safety event. You run it, you find the system cause, and you change it so the next person does not get hurt. (See related: Near-Miss Reporting Without Blame.)

For everything short of that, use the tree below.

Start here: did anything meaningful actually vary from plan?

A post-mortem is worth running when reality diverged from what you expected, in either direction. If the job went exactly as planned, there is usually nothing to learn. Ask:

• Did something go meaningfully wrong (a callback risk, a blown timeline, an angry customer, a loss)?
• Did something go meaningfully right (it beat expectations and you do not fully know why)?

If neither, move on. If either, keep going to the triggers.

The triggers: any one earns a review

Run the post-mortem if any of these is true. You are not looking for all of them.

• It could recur. The cause is baked into how you work, so it will come back on another job unless you change something. This is the strongest trigger.
• The lesson transfers. What happened here would apply to other jobs, other crews, other customers. A lesson that only ever applies to one freak situation is not worth a meeting.
• The cost or near-cost was high. A job that nearly lost a big customer, nearly caused an injury, or ate a serious hit is worth understanding even if it feels like a one-off. High stakes lower the bar for review.
• The win was real but unexplained. You want to repeat it, and you cannot repeat what you cannot name. Reviewing a success is how you turn luck into a standard.

When to move on without one

Skip the post-mortem, honestly, when all of these hold:

• The variance was minor and self-correcting.
• The cause is obvious and already fixed (a one-time supplier stockout that is already resolved).
• It cannot plausibly recur and teaches nothing transferable.

Moving on is a legitimate decision, not laziness. A shop that reviews everything reviews nothing well, because the crew tunes it out. Spend the attention where the lesson is.

If it is a yes, keep it proportional

Deciding to review does not mean a two-hour meeting. Match the depth to the stakes:

• Small lesson: a five-minute conversation with the one or two people involved, and a note.
• Serious job: a proper sit-down with everyone who touched it, working the four questions of a real after-action review. (See related: The After-Action Review That Turns a Bad Job Into a Lesson.)

The bigger the stakes, the more structure. But even the biggest job's review is measured in a slice of an afternoon, not a day.

The recap

1. Safety event? Automatic yes, hazard already controlled, find the system cause.
2. Did anything meaningful vary from plan, good or bad? If no, move on.
3. Any trigger true, could recur, lesson transfers, stakes high, or an unexplained win? Review it.
4. All-minor, obvious-and-fixed, cannot-recur? Move on without guilt.
5. If reviewing, size the review to the stakes, from a five-minute talk to a full sit-down.

The judgment to bank: the goal is not more reviews, it is catching the jobs that carry a lesson before the lesson walks out the door.

References

• Trade-standard practice for post-incident and after-action review
• See related: The After-Action Review That Turns a Bad Job Into a Lesson; Near-Miss Reporting Without Blame
• Plan-Do-Check-Act improvement cycle, standard continuous-improvement method