Glossarytaught in M6.04
Hindsight bias
Also called hindsight, knew-it-all-along effect.
Remembering a past uncertainty as having been more predictable than it was.
It corrupts learning, because a decision that turned out badly is remembered as obviously wrong and one that turned out well as obviously right, when both may have been reasonable given what was known.
Only a contemporaneous record defends reliably against it. A decision journal written at the time, stating the reasoning and the probabilities, can't be revised by memory.
Judge the process from the record, not the outcome from memory.