I want to change the not want to self-improve part since a life lazing around seems pretty meaningless, though I am also pretty contented to be a lazy bum.
Sorry for reiterating this point, but I still don't understand the question. You seem to either have no reasons or have relatively weak reasons for wanting to self-improve, but you're still asking how to motivate yourself to self-improve anyway. But you could just not. That's okay too. You can't argue self-improvement into a rock. If you're content to be a lazy bum, just stay a lazy bum.
r/Fitness does a weekly "Moronic Monday", a judgment-free thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. I thought this seemed like a useful thing to have here - after all, the concepts discussed on LessWrong are probably at least a little harder to grasp than those of weightlifting. Plus, I have a few stupid questions of my own, so it doesn't seem unreasonable that other people might as well.