Where should the armor go?
In World War II, officers counted bullet holes on the bombers that came back. The body and wings were riddled with them; the engines had the fewest. Their plan: armor the places getting hit.
Where would you put the armor?
Before the reveal comes the argument. A partner would push you on:
Which planes did they actually count?
If a plane was hit in the engine, where would it be now?
THE REVEAL · Mathematician Abraham Wald saw the flaw: they only counted planes that survived. Planes hit in the engines mostly never came back. His advice: armor the places where the returning planes had the fewest holes.
THE PATTERN · Only the Survivors: judging by what made it through, and forgetting what didn't.
