Originally Posted by regwec
It's better, in my opinion, just to create another reason for his defeat. It doesn't need to be Kryptonite; it can be fear for the people he loves or an overly rigid sense of duty.
It also comes down to the threat he is up against. Superman can still be Superman in every sense of the word. For example using all of his powers and they aren't making sufficient inroads, ala against Doomsday or Parasite absorbing attacks.