During World War II, the US was losing lives as planes were being shot down in enemy territory, so they took on an initiative to improve the armor on the planes.

They started with a survey of planes that had been damaged in combat. They charted all of the bullet holes, and a clear pattern emerged.

A few areas were taking almost all of the bullets, and other areas had almost none.

Thus, it was obvious, they had to reinforce the areas that were taking all of the bullets, and they’d be good to go.

Right?

Of course not.

The bullet holes on the damaged planes didn’t represent the areas that were most prone to getting shot. They represented the areas where the plane could be shot, and still survive.

Any planes that were shot in the areas that didn’t show bullet holes must have failed to return from their trip.

The US needed to reinforce the areas on the heat map where they didn’t show any bullet holes. Not the opposite.

-Brandon

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