Miyamoto Musashi (played by Toshiro Mifune in the Samurai trilogy) wrote in the Five Rings of Power that sometimes when you defeat a man, he doesn’t feel defeated, so you have to hit him once or twice more in order to convince him that he’s done and should stop fighting.
Unfortunately, the Derp State is more like Jason from “Friday the 13th” or Freddie Krueger. When you kill them, they just keep coming back. That’s another reason I call them Satanic.