Pessimism Bias

The tendency to overestimate the likelihood of negative outcomes, seeing the worst-case scenario as the most probable.

While some pessimism is protective, this bias goes further — anxiety and past negative experiences can make threats seem more likely and severe than they are.

• Assuming a new project will fail before it's even started.
• Expecting the worst outcome from a medical test despite low statistical risk.
• Avoiding investment opportunities because 'the market will crash.'

• Check base rates — how often does the worst case actually happen?
• Balance worst-case thinking with best-case and most-likely-case scenarios.
• Track your predictions to see how often your pessimism was warranted.
• Distinguish between productive caution and paralyzing pessimism.