Post-Mortem

The post-mortem — disciplined study of what went wrong — is one of Kyle’s load-bearing investing and learning themes, and the subject of his published essay What’s In a Post-Mortem (“Learn To Keep From Dying”). His research frames it as a practice that migrated from medical autopsies to manufacturing, software engineering, and startup investing, whose core question is simply “what went wrong?” — which first requires the Spirit of Humility to acknowledge that something went wrong. The thesis is that the biggest blocker to learning from experience is not method but willingness, and that done right a post-mortem (and its sibling the Pre-Mortem) lets you learn as much from success as from failure.

The idea recurs across Kyle’s reading. In the Berkshire Hathaway Annual Letters, Charlie Munger emphasizes “the study of mistakes rather than successes,” and Buffett asks why post-mortems “useful for hospitals and football teams” aren’t applied to businesses and investors — a frame Kyle applies to his own hindsight-error reflections (e.g. a post-mortem on Scalefactor). Amazon Unbound supplies the operational version: Amazon’s “correction of error” reports and the “five whys.” The Founders notes Peter Thiel’s failed Smart Calendar as “a paid crash course,” paired with David Sacks’s pre-mortem (“if I were running eBay Payments, what would I do to kill PayPal?”). The Idea Factory offers Bell Labs’ failure taxonomy — the waveguide as a “mistake of perception” vs. the Picturephone as a “mistake of judgment.”

Context: A post-mortem (or “retrospective”) is a structured after-the-fact analysis of a project or decision to surface causes and lessons; the term comes from medicine, and the practice is now standard in fields like site-reliability engineering (“blameless post-mortems”).

Where this appears

• What’s In a Post-Mortem - Research — the full research doc behind Kyle’s essay; post-mortems as a discipline gated by a Spirit of Humility.
• Berkshire Hathaway Annual Letters — Munger’s “study mistakes, not successes”; Buffett on post-mortems for businesses; Kyle’s Scalefactor hindsight-error note.
• Amazon Unbound — Amazon’s “correction of error” reports and the “five whys.”
• The Founders — Thiel’s Smart Calendar as a “paid” post-mortem; Sacks’s kill-PayPal Pre-Mortem.
• The Idea Factory — Bell Labs’ “mistake of perception” vs. “mistake of judgment” failure taxonomy.