People don't tend to post this stuff, but I've seen a few. Most were due to not passing the background check or not meeting their school's criteria to participate (GPA, grade level, etc.).
One guy a few years back said that he accidentally cursed during his interview and thought that that is why he didn't get in. Probably for the best on that one.
Some others said that they only wanted a specific job or they didn't want to do it. One said she only wanted to do characters and nothing else. didn't pass the audition. Not that that's a bad thing because you shouldn't say you will do anything if you don't mean it. You know, that entire "be careful what you ask for" thing? So if there is something you really don't want to do, it is a bad idea to say that you are willing to do it... cause if you get it, then you got it.
They have so many positions to fill, 99% of the people who interview have nothing to worry about.