I think our enjoyment of an activity depends on how we see our progress.

If we keep struggling with it, we will hate it, even if we thought we would like it at first.

We could also begin to enjoy an activity if we see ourselves progressing in it. When you see your improvements, your brain probably releases dopamine (or another one of those addiction chemicals) and that makes us want to do it more (to taste that sweet taste of victory/progress).