This is called ergodic theory, the more you repeat an action that could result in catastrophe, the likelihood of that catastrophe occuring will be close to 100% if the number of events is high enough.
Right, but it's easy to conflate two very things here:
"What are my chances of dying in a climbing accident", and
"What are my chances of dying today if I go climbing".
If you are on a plane, you* have a lower risk of some kinds of cancer than the airline staff do. This has nothing to do with the flight you are both on, and everything to do with accumulated flights
"you*" = for most people, i.e. barring a counteracting risk factor.
