I quit flying years ago. I don't want to die with tourists.
Do not quit! Hundreds of times I have watched people throw in the towel at the one-yard line while someone else comes along and makes a fortune by just going that extra yard.
All ballplayers should quit when it starts to feel as if all the baselines run uphill.
I think one of the reasons people quit is because they're afraid they won't be able to get better and better; that they have to come to a zenith of some kind.