Youth is a blunder; manhood a struggle; old age a regret.

Looked at from any single stage, the others tend to be judged harshly. Early life is clumsy because nothing has been learned yet, the middle is effortful because that is where the work sits, and the end can look backwards and find plenty to wish had gone otherwise. Something in that reading is true and it is not obligatory. Regret is common at the end and it is not the only thing available there.

Whatever stage you are in, take it on its own terms rather than measuring it against a better version. And do the thing now that you would otherwise be listing later.