[blakeyrat]

If the solution to the problem relies on human beings being fully-informed, entirely competent, and never making mistakes-- it's not a very good solution, IMO.

Yes, people should maintain backups. But if people don't, for whatever reason (maybe they've never heard the word "backup" before; maybe they typed the wrong command and thought they had backups all along, etc.) shouldn't be screwed if something goes wrong.