The bullets that killed planes didn't leave holes on returning aircraft. Abraham Wald saw what others missed.
It's 1943. Allied bombers are being shot down over Germany at alarming rates. The Navy needs to add armor—but armor is heavy. Where should it go?
In 1943, the Statistical Research Group (SRG)—a classified program at Columbia University—assembled America's brightest statisticians to help win the war. Among them was Abraham Wald, a Hungarian-Jewish mathematician who had fled Nazi persecution.
The military presented a problem: returning bombers showed damage concentrated on the fuselage and wings. The engines? Almost untouched. The obvious solution: reinforce the fuselage and wings where the damage was.
Wald recognized what everyone else missed: the data was only from survivors. Planes hit in the engines, fuel systems, and cockpit didn't return—they were lying at the bottom of the English Channel or in German fields.
The "clean" areas on returning planes weren't safe—they were fatal. A plane can fly home with holes in its fuselage, but a single bullet in the engine means it never returns.
The military listened. They armored the engines, fuel systems, and cockpits. Bomber survival rates increased dramatically, and Wald's insight continued influencing aircraft design through the Vietnam War.
We celebrate Zuckerberg, Musk, and Bezos. We study their habits, read their biographies, and copy their strategies. But for every unicorn, there are thousands of identical failures we never hear about.
Below are 100 startups. Only 10 survived. When we only see the survivors, we develop dangerously wrong ideas about what leads to success.
Mutual fund advertisements boast impressive returns. But they only show funds that still exist. Failed funds are quietly dissolved and vanish from the records.
Research by Morningstar found that including defunct funds reduces 10-year returns by approximately 1% annually. Over decades, this compounds into massive wealth differences. That "market-beating" fund manager? Their competitors who failed worse are invisible.
For every success story, ask: "How many tried the same thing and failed?" If you can't find failures, your data is incomplete.
Don't just study successful people or companies. Study failures intentionally. What did they do wrong? What did they do the same as successes?
Before copying a strategy, ask: "What percentage of people using this strategy succeed?" A 10% success rate means 90% failure rate.
If success had a simple formula, everyone would follow it. The very existence of a "secret" suggests survivorship bias is hiding the failures.
Wald's insight saved countless lives during WWII, but his impact extends far beyond. His work on sequential analysis revolutionized quality control in manufacturing. His statistical methods influenced everything from clinical trials to economic policy.
Tragically, Wald died in 1950 when his plane crashed during a trip to India—an ironic end for the man who taught us how planes should be armored. He was 48 years old.
His lesson endures: the data you can see is shaped by what's missing. The holes in returning bombers told a story—but it was the planes that never returned that held the truth.
Next time you see a successful person, a thriving company, or an impressive statistic, remember Wald's question: What's not here, and why?