Never wrong; rewrites history
A decision they pushed fails. In the post-mortem they recall having raised concerns at the time, and their account of the meeting doesn't match yours.
Rule out first
Ordinary memory reconstruction; everyone does it. Whether they really did raise doubts somewhere you didn't see. A blame culture where admitting error costs a career.
What could explain it
Hindsight bias: Sincere and mild. Shown the email from the time, they accept it with some surprise.
Cognitive dissonance: Being competent is central to who they are, so the memory bends instead of the self-image. Shown the record, they reinterpret it ('that's not what I meant') but don't attack you.
Motivated reasoning: The revision tracks their incentives closely: bonus, reputation, next role. Change the incentive and the story changes.
Grandiose narcissism: It holds across many decisions: wins are theirs, losses belong to others. Evidence brings irritation or contempt, not reflection.
Gaslighting: They don't just misremember; they tell you that you are misremembering, mostly when you're about to hold them to something. Over time you start doubting your own notes.
A next move
Keep notes at the time and, once, show the record calmly. Acceptance means ordinary bias; reinterpretation means dissonance; contempt points to narcissism; a counter-claim that your memory is the problem points to gaslighting.
If it’s you
Which version of events would I be ashamed to remember? Is that the one I've lost?