Retrospective vs Post-Mortem vs Lessons Learned

Quick answer

Retrospective is the regular process-review ritual; Post-Mortem is the after-incident/project review — the difference, and when each applies, below.

The 30-second answer

Retrospective: The regular process-review ritual. Post-Mortem: The after-incident/project review. Lessons Learned: Documented takeaways from experience. The difference matters when you’re picking the right tool for the situation.

Side by side

Retrospective in depth

The regular process-review ritual — use it improving how the team works.

Post-Mortem in depth

The after-incident/project review — use it learning from completions and failures.

Lessons Learned in depth

Documented takeaways from experience — use it capturing for next time.

Which one when

• Use Retrospective when improving how the team works.
• Use Post-Mortem when learning from completions and failures.
• Use Lessons Learned when capturing for next time.

In practice they coexist — the skill is knowing which fits the moment.

Bottom line

Retrospective is the regular process-review ritual; Post-Mortem is the after-incident/project review — the difference, and when each applies, below.

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