Learning from your mistakes is always expensive, but it is for this reason that the experience you have gained will never be forgotten by you. And since you have already analyzed the mistakes you have made, you can move forward by learning the wisdom of trading.
I think it only depends on the damage or the activity that we are doing, as you know there are still light activities out there but to do them not right is always considered as a mistake. A bad experience is a bad experience, so usually we don't want our selves to remind us on it again because it can only make us feel sad or stressed. But I don't really know, maybe there are still some that are like that you said. Maybe it makes them to stay motivated.
For some, they can analyse their mistakes but came into a conclusion that maybe they are not really meant for trading. This also makes them to move forward but in another direction this time.