I wish I had stuck with it when I started trying to produce in highschool, and again early in college those few times. I didn't seriously get into producing until maybe 3 years ago, wasting lots of valuable time. Luckily, I spent much of that time DJing, so I was still learning about how tracks were built and meant to sound, etc.
I also wish I hadn't associated myself with a certain "easy" label early on in my learning. I was excited just to get a track signed, but they weren't really a good label, my production was still crap, and nothing really came of it. I should've just put those songs out for free. Oh well.