In college I never had a backup for any of my computers. I knew about backups. I knew I should have one — especially given I was on Windows for the first couple of years. But I never had one. I did constantly reformat my computer (Windows), so I had backups of my working files and pictures, but that was about it.
Which really sucked, because a couple years into college my computer was stolen. Amazingly I didn’t really lose much. I lost some images, and some files, but not a whole ton of stuff.
And yet, when I got a new computer a few days later, I again didn’t backup. It wasn’t until I was out of college and getting heavier into photography when I started to back up. And then I started to get really into the nerdy side of backing things up.