I think you have to psyche yourself out and just make one.
Whatever competition this might be, I'ma make the best goddamn RTP game ever made in the history of mankind.
That's why I have been waiting for a contest.
I don't think I can properly psyche myself to make a game on self-determination alone, and an organized event with a timeline/deadline is likely to force me straight into the process with enough of a chance of actually seeing it through.
Either way, I feel that once I can finish making a first game, it will be a lot easier in my mind to work through any other game idea I happen to have, no matter how convolutely large my aspirations for it are.