Why? I don’t see the point in it. I played through the personal story with all of my chars, partly to get rid of the story symbol in the upper right corner, partly for the loot (and partly because I’m a masochist I guess) and now I have the symbol back and can’t get rid of it. Furthermore, I can’t do the story achievements with my warrior for example, because I only did the steps with my necromancer and I have the achievements unlocked. This does not make much sense to me imo.
Inb4 you’re not forced to do the story with every character. – I know I’m not, I still don’t see the point behind the system and I’d very much like to see the living story steps made account wide.