I went of fishing o'dark thirty and locked the door as my wife was sleeping. Turns out she could not get it to unlock from the inside. Good thing I limited early and found her still locked in. Took the lock apart and found nothing wrong but did lube it. I think a small rug got under the door and jammed it enough to keep things from working.
I know a guy that had a brand new camper and was stuck inside with three adults. This was before escape hatches so he had to remove a window to get out. Took awhile and he got cut up going out.