[Disney's Hercules] Why didn't Hades just kill Hercules himself?

Maybe this has been discussed before, but I'm unaware of past answers, so I'll just ask away:

Am I the only one who wonders why Hades didn't just kill Hercules himself and be done with it? I mean.............as strong as he was, Hercules was still a mortal human before he saved Meg, and Hades was a literal deity. Couldn't he just...........smite him?