Firstly, I am busy most of the year with school. Secondly, when I am not busy with school, I am busy with conventions and working on my own projects. Thirdly, I'm just lazy lol
But really, the main reason I don't want to do commissions is... I just don't enjoy doing them for extended periods of time. I mean, unless they are characters I already know and love, I know I'll either end up spending too long on them without producing the desired result, or just end up half-assing them to avoid that from happening in the first place lol...
Drawing is something I want to enjoy doing. I fear that if I don't enjoy what I draw, I'm going to end up getting tired of drawing, period. I don't want to lose myself from the one thing I am relatively good at. Commissions can really suck the soul out of an artist's drawings... I don't quite know what I mean by "soul", but it's that extra oomf that lures and captivates people. I've seen this happen in other people who do commissions for a long long time... Sometimes, they seem to even degrade in skill. I don't know, I don't want my pieces to imbue "I don't give a f*ck anymore".
This is why I am reluctant on pursuing the art industry. I don't trust myself to be able to artistically thrive in a commercially demanding environment.