There's little incentive for the repair processes to be perfect. There would actually be zero incentive after we reproduce - and some species are exactly like t

There's little incentive for the repair processes to be perfect. There would actually be zero incentive after we reproduce - and some species are exactly like that. The moment you reproduce, you die. Humans, being a social species, might have pushed evolution towards trying to repair a bit more than it should. Older humans can still contribute - sometimes a lot - to the group. Older males can still reproduce in many cases.