The image is a reference to the seminal work done by statistician Abraham Wald in World War II: the military planned to add armor to the parts of bombers that had the most bullet holes; Wald noted that only bombers that survived their mission could be examined, which means the parts without bullet holes were actually the most vulnerable and needed armor. This is called “survivorship bias”
Stratechery Daily Update 2017-01-03, January 3, 2017 at 11:31PM
I’m surprised how widespread the Survivorship bias is, even 70 years after its discovery.