It's a good question.  Each of the things I've put up on sharecg has been something I made because I thought I had a need for them, or a possible use, but over the years I've also found some of my ideas changing.  Some of my first were done in a day or two, and they look like it.  The last items I put up were a week or more, a lot of head scratching, a few "Ah-Hah!" moments, but for the ideas I have now, they serve better. 

But I'm aware of the time it can take, and how many times you can go over an item and see things you don't like, sometimes doing it over and others just refusing to see it.  I'm well aware I'm a long way from anything of commercial quality, but again, it serves my purpose, even if that purpose was to just kill time and see what my mind comes up with.  Probably this puts me in a different position than most would be, because once I have the model, it's what I want, and if someone else would maybe like it, I post it.  I can easily understand that eventually someone might expect or wish for a little compensation for the time and effort, but so far, I haven't felt that myself.  Ockham's suggestion of the "donate" button might be a way, but I have no idea how successful that is in practice.  It might be worth exploring.

Or, if you have something you feel worthy of going commercial, give it a try.  There's nothing saying you can't continue to make freebies too.

Doric

The "I" in Doric is Silent.