Youtube screwed me over this way. They closed my account for "copyright strikes" or some such nonsense because of some videos I posted from a renfair that happened to have music in the background. As if someone is going to pirate music from someone's amateur video. I wouldn't have had any problem removing the videos in question but no, i was never given the opportunity. Everything was just deleted. I didn't do anything "professional" with youtube, using it mostly as a means to share videos with friends and family though many videos were public as well. There were thousands of videos that I had spent too many hours to count uploading over the years...
Anyway, I always keep copies of my own stuff so it was more of a massive inconvenience than a painful loss. I feel sorry for people that don't keep their own backups though. If I had truly lost all that video it would have been devastating.