Only available dates for a competitive program ... I already had interviews scheduled.... so I cancelled one in a location that I didn't particularly care for.
Program wanted 3 interview date choices and took a month to confirm, by then I had cross country interviews surrounding my 3rd choice, which is the date they confirmed, so I cancelled.
I cancelled one after I got 10+ other offers, because it was in a location I decided wasn't for me. I also declined a few interview offers prior to scheduling because the programs were (1) not good fits for me, (2) expensive to travel to, AND (3) did not pay for the hotel room.
