My dad flew 30 some missions over Germany. The cohort he went over with had an 80% casualty rate. Some missons had a 10% death rate. He could do the math, and assumed he was going to die.

(Obviously, he did not die, since I exist, but he came literally within a couple inches.)

When he arrived back in the US, he was bemused by all the stuff back home people worried about. He thought "what the heck are you worried about, you're going to live another day!"