User blog comment:Madman97/You know what really grinds my Wabbajack's? S3E1: I can't kill these guys/@comment-25109952-20131025182427/@comment-1600847-20131026010022

Actually, one youtuber installed a mod to make all characters killable. He went to find Delphine in Riverwood for the Horn of Jurger Windcaller, she was dead in the Riverwood Inn. He resurrected her, then she turned up dead on the road to Kynesgrove, killed by a Spriggan.

Those are just two examples. Trust me, the radiant AI makes it unpredictable. If quest characters can die, without any way of the player preventing it, console players would stop playing after a very short while or have to re-start the game over and over again. Morrowind's "everyone can die" system only worked because the important characters never moved, or did so by "teleporting".