Well, because loosing the beginning can be really depressing so you don't want to have anything to do with that anymore. I'm more happy for that the Dev can continue writing at all.
Some 20 years ago I had a bad hard disc crash, nothing to do but to scrap my old and in with a new. Then I started my backup program to take back data from my external disc. I had taken backups every week, so no problem. It was just that every backup was crap, I had never tested my backups (do that!). I lost my novel, nearly finished, about 50 short stories and some hundred poems. I haven't written a single line since then. I've never gotten back my lust to write again. So kudos if we get something at all!!!