Post-mortem process

A project post-mortem is a process, usually performed at the conclusion of a project, to determine and analyze elements of the project that were successful or unsuccessful. The Project Management Body of Knowledge (PMBOK) refers to the process as lessons learned. Project post-mortems are intended to inform process improvements which mitigate future risks and to promote iterative best practices. Post-mortems are often considered a key component of, and ongoing precursor to, effective risk management.

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https://en.wikipedia.org/wiki/Postmortem_documentation