Bullet Points

The year is 1943. The U.S. military has a deadly serious problem. Their planes keep getting shot down over enemy territory, and nobody can figure out why.

So they do what any reasonable organization would do - they gather their brightest minds in a giant hangar. We're talking mathematicians, engineers, and military strategists, all staring at battle-damaged planes with increasingly furrowed brows.

These experts spent days mapping out every single bullet hole on the returned aircraft. Their diagrams showed clear patterns - the wings and tail sections were absolutely peppered with damage. Like someone had played the world's worst game of connect-the-dots.

Looking at their beautiful charts and graphs, these brilliant minds reached what seemed like an obvious conclusion: 'We need to add more armor to the wings and tail! Look at all these holes!' The generals nodded in agreement. The engineers started drawing up plans. Everyone was so damn proud of their logical deduction.

Enter Abraham Wald, a Jewish mathematician who's probably wondering if he escaped the Nazis just to watch people be this dense. He looks at their meticulously gathered data and asks one simple question: 'Where are the planes that got hit in the engine?'

Nobody had an answer to that.

See, they were only looking at the planes that made it back. The ones with holes in the engine were scattered across Europe in tiny pieces. This would be similar to concluding that hospitals make people sick because you only count the sick people inside them.

The best part? This wasn't even Wald's field of expertise. He was a geometry guy who just happened to be really good at pointing out when people were being dumbasses. The people in the hangar finally learned that they were so focused on what they could see, they completely forgot about what they couldn't.

Today, you'll find this story in countless articles about survivorship bias, each one citing the same example about the bullet holes in the planes.