I’m a tinkerer; it’s in my nature. When it comes to game mechanics, I like to pick them apart and put them back together. This is doubly true with games that I’m designing myself; I’m never really satisfied. I always come up with better ideas, more ideas.
Well, not always better; sometimes it’s just more.
There’s a quote I heard a while ago. I think it might have been Paul Tevis (though it’s possible that he, too, was quoting someone) who said, “The better is the enemy of the done.” I try to live by those words, but it’s hard sometimes. I want my games to be perfect, but that’s not the whole reason: I also just enjoy tinkering. I like to monkey around with systems and rules, I like to twist settings and make them do new things. I’m constantly coming up with ideas — in the car, at work, in the shower, on the crapper — that need an outlet, and sometimes something that I’m working on is a convenient target for these ideas.
My point is, this is a problem. Some amount of tinkering and perfectionism is good; you want your game (or novel, or haiku, or Angry Birds knockoff) to be as good as it can be before it goes out for public consumption. That’s fine.
But at some point the thing just has to be done.