I've recently noticed that having auto-save functionality no longer makes me feel "safe". Previously, if a program automatically saved every 5 minutes or so I was completely confident that I could never lose more than 5 minutes work which seemed good enough. Now however, I want more than auto-save, I want version history.

If I can't go back and find a previous version then I can't be confident that the next time I save it won't corrupt things and I'll lose everything. Odd really.