Superman is supposed to have 3 major villains. Lex, Brainiac, Zod, but Lex and Brainiac have been first villains of the JL for years and after Superman, Zod seems to want to turn him into some kind of rival. Luckily there is someone who is giving importance to Mongul, because at this rate I see Superman fighting against bag thieves.
because you think that Superman's villains end up in the JL while the rest of the heroes keep their villains.