> A human being can drive a million miles without a serious accident

A million miles sounds like a lot, but it isn't. The average American drives 12,000 miles annually. Assuming a driving career of 52 years (from age 18 to 70), the average American will drive 624k miles. So the lifetime chances of getting into a serious accident are not exactly small.

(I don't know how to calculate the probability here, actually. Is 624k/1M the lifetime probability of getting into a serious accident?)