My previous phone was having power issues and hard crashing when you’d plug it in, and it one time forced me to factory reset and I hadn’t backed up any of the data that was on it. All the pictures I’d taken in two years, any files I downloaded, app data… gone. Couldn’t tell you what all I lost, nothing too important, but that sucked.
I’ve also had the opposite… we were migrating our file server and did a preliminary move, then when it was time to prep to go live, I just… copied all the data over from the old one to the new one to speed things up.
Unbeknownst to me, there was “version control” managed by just moving files to a different folder. Well, guess where all the files were when I combined with the month-old stale data?