I actually only applied once and got in. I still had a full time job when I applied, I had no connections to the YC community prior to applying... and I don't know if the YC partners know this, but I actually did the entire application + video in <30 minutes.

I remember doing the app from my mom's garage when my girlfriend was like, "hey Ryan, don't you think you should spend some more time on this before you send it in if it's important?" My response to her was that there was probably no way I was going to get in so I didn't want to put that much effort into the application.

I might be speaking for YC, but I think the thing that was more interesting was our actual product and where we'd gotten it to more than a beautiful polished application and video.