People (some people) deal very poorly with far future deadlines, where "far" ranges from "after this conversation is over" to "months from now." Middle class Americans are typically trained to be a little better at this than humans are born to, but at the end of the day you're running Well-Educated Professional 2011 on hardware designed to be minimally capable of executing SimianOS.

There's also a spectrum of, shall we say, commitment to one's application which is orthogonal to quality of the application. If I were to ever apply, that would be a Certified Big Deal for me personally, but for someone running a successful business, speaking to investors, and in the middle of hiring engineer #3, this might be just one more thing on the ToDo list. That doesn't necessarily make my business a better fit for YC than her's.

Actually a surprising number of the best startups we've funded applied on a whim at the last minute. IIRC David Rusenko of Weebly applied in the last half hour without even having had time to tell his cofounders that he was.

Judging by the flood of last-day applications, in spite of PG's advice to apply early, a reminder is still needed: http://twitter.com/#!/paulg/status/123509842412445696

I'm not sure why you're getting downvoted. I thought the same thing.