From the other comments here this seems like a common sentiment. I do indeed do things which are not enjoyable in the strictest sense, as you phrase it. However I do still think my original comment is true, so perhaps there is some finessing to be done here. I'm not sure I have the answer though.
Perhaps there are different kinds of 'enjoyment'. And perhaps I'm personally willing to accept some immediate suffering because I know I'm pursuing a greater enjoyment.
I'm certainly not advocating for (constantly) pursuing in-the-moment unbridled hedonism.
Something which may be related to this is the idea of type 1 fun and type 2 fun. I'm not sure where I heard this, but few people I talk to have heard of it.
Type 1 fun is the kind of fun which is enjoyable in the moment. For example, computer games and watching youtube videos.
Type 2 fun is the kind of fun which is enjoyable upon reflection but not necessarily in the moment. For example, running a marathon, certain moments of trial/despair when working on a big project.
When I first played Factorio I played it for about a week solid. I loved it. After that I could put it down and do other things. I now play it for a couple of days every couple of months when the mood takes me. This is type 1 fun for me.
I'm certainly glad a ran a marathon, and it is a very happy memory, but no way in hell am I going to do that again. Very much type 2 fun.
Some comments (not necessarily the one I'm replying to) seem to inversely correlate enjoyment with how hard a task is. The harder a task is the less likely it is to be enjoyable. Is this true? It certainly isn't my experience, but maybe I'm odd as I originally suggested.
Something which has also driven me is boredom. Being a freelance developer has given me a lot of free time. Certainly for me, type 1 fun only goes so far in conquering that boredom. Sure, play computer games for 6 months, but then that gets boring too. At least it did for me. Then what?
Then, for me, type 2 fun starts to look more appealing. Perhaps I should build a house? Sure its going to be hard, but I'm practical and I like leaning new stuff. Plus I'll be outdoors, and at the end of it I'll have a house. (FWIW, I actually did this)
Perhaps that's just being an "up" kind of person. I think it is also believing in one's abilities.
I don't think this is a cohesive point with a strong conclusion, but perhaps this series of paragraphs is useful in furthering a discussion.