I think I'm simply lazy.

But I've been able to cultivate caring about particular goals/activities/habits, and then, with respect to those, I'm not so lazy - because I found them to offer frequent or large enough rewards, and I don't feel like I'm missing out on any particular type of reward. If you think you're missing something and you're not going after it, that might make you feel lazy about other things, even while you're avoiding tackling the thing that you're missing head on.

This doesn't answer your question. If I was able to do that, then I'm not just lazy.