Beyond the obvious reason that practice makes you faster/better at anything, on top of that I've improved my tools and methods drastically since that first issue (which was created so inefficiently it's a wonder the thing even exists).

The rewards were intended as a 'thank you' sort of thing, but they really benefited me a lot since they gave me so much practice. I'm still pretty early in my artistic development (I hope), so I look at a lot of them and think 'Damn, I couldn't have pulled that off a couple years ago'. Which is cool.

That said, I'm still not anywhere near as fast as I want to be