Dude, Azura, a Daedric Lord, is literally responsible for the Nerevarine's existence. You act as if anyone could have literally jumped up and sastisfied all of the prophecies and whatnot; while more than one person fufilled SOME of them, they're...dead...now. If I interpret info correctly the Nerevarine is "http://www.imperial-library.info/obscure_text/nu-hatta.shtml," as one Nu-Hatta has said, which means he's practically a god, if he literally isn't one. I'll provide you the link to this document soon.
edit: link added.
Well, from what I recall, souls of mortals on Nirn usually end up going to the Dreamsleave... and sometimes they get reused... so I suppose Azura was banking on the chance that Nerevar's soul would slip out of the Dreamsleave and back into Nirn. I don't think Nerevar was a 'god,' he didn't use Kagrenac's tools like Vivec, Almalexia, Sotha Sil, and Dagoth Ur did.