The bias that can cause catastrophe

Imagine a pilot is taking a familiar flight along a known route, during which the weather takes a turn for the worst. She knows that flying through the storm comes with some serious risks – and according to her training, she should take a detour or return. But she has flown the same route before, in similar weather – and she hadn’t experienced any problems then. Should she continue? Or should she turn back?

If you believe that she is safe to fly on, then you have fallen for a cognitive quirk known as the “outcome bias”. Studies have shown that we often judge the quality of a decision or behaviour by its endpoint, while ignoring the many mitigating factors that might have contributed to success or failure – and that this can render us oblivious to potentially catastrophic errors in our thinking.