Because creative thinking isn't usually logical, it can be hard to gauge how good an idea really is when you come up with it. Instead, better to just do it, share it, and then make your judgments.
Designer Frank Chimero reminds us that our brains are not computers in a neat little pseudo-comic about how ideas work. Simply put, a computer makes logic-based relational assumptions (like "you bought this can opener, so you might enjoy this can of bean mush") whereas your brain makes alogical — but often meaningful — assumptions. The ideas you have don't necessarily make logical sense when you think of them because they're not necessarily logical in the first place. Frank's comic creatively elaborates on how you're better off just doing things since your brain is alogical and can't really make a sound value judgment right when the idea hits:
Be sure to hit up Frank's site for the full, very interesting and entertaining comic.
Sense vs. Nonsense, or How Not to Be a Dumb arse Super-computer [Frank Chimero via Swiss Miss]