You're collecting ability, because being able and good at something makes people happier. We could have called it skill, talent, competence: they're all the same thing. What is guitar for one person might be recreating famous battle scenes in Lego for another.

A shortcut to unhappiness is doing things that you're crap at. So if someone tells you they hate a class or a job, it's likely to be because they're not very good at it. It's wrong to think things have to be really hard in order to be worthwhile.

If you're not sure what you're good at it can help to ask someone else. Or a few people. It might be that everyone knows you as a very good listener, or that you're a great cook. Or that you have a great sense of style. Whatever it is, identify it and then do more of it. And if you know you're good at something, just keep stretching yourself to be better. It will make you happier!