Hindsight bias
Once you know the outcome, you believe you knew it all along.
Past outcomes feel inevitable in retrospect. The 2008 crisis 'should have been obvious.' The success of Apple 'was clear from the start.' The collapse of Theranos 'showed every sign.' At the time, none of these were obvious.
The bias corrupts our memory of what we actually believed and predicted. We update our recollections to match the outcome, then judge our past decisions against the new (false) memory of having predicted correctly.
For operators, the practical defence is a decision journal. Write down what you believe and predict at the time you make a meaningful decision. Refer back when the outcome materialises. The gap between what you actually thought and what you remember thinking is hindsight bias at work.
Examples in the wild
After every major failure, the post-mortem reveals 'obvious' warning signs that weren't obvious at the time. The honest post-mortem distinguishes signs that were genuinely available from those that became visible only afterward.
Every bull and bear market in retrospect 'should have been predicted.' At the time, the signals were ambiguous. Hindsight makes prediction look easier than it is.
Most relationship breakdowns get explained in hindsight as 'I should have seen X coming.' Sometimes that's true. Often it's hindsight constructing a coherent narrative.
Hindsight bias is one of the mental models we apply through real cases inside the Pareto MBA — a part-time program for professionals who want to think clearly about business.