While players (of some quality) are a necessary condition of a good game, they're not sufficient. As has been pointed out, most games die when the GM stops updating.
I know real life sometimes calls us, but for me 99% of the time, my muse fluctuates rapidly. I'm not looking to make any excuses, mind you, merely helping to isolate problems and build a better forum game community. For some reason, my writing muse will shift sometimes multiple times a day. It usually depends on what media content I consume. Usually. Sometimes I'll want slice of life fantasy anthro stuff, so I'll write that. Other times, I'm in the mood for pure fantasy adventure, so I'll write that. Other times, I hunger to write a space opera, so that will be a suggestion game I throw up there.
Obviously, the necroposting rules here are laid back (unexpected given how totalitarian the forum administration itself is), so GMs like myself can always revive an old SG or game thread. But that doesn't solve the "shifting muse" problem that I, and likely a few other GMs, struggle with. I think what MIGHT help with that is opening a Google Doc and writing a one-shot or word-salad story about that idea, and see if it holds. If you're writing it for a day or more, it might be a sign to run a SG. If you forget it at after a paragraph, you probably shouldn't run it.
Am I making sense?