Plot-Induced Stupidity

Description
PIS, short for "Plot-Induced Stupidity" is a term used to refer to events in a story that contradict a character's normal capabilities for the purpose of the plot. For example, if a generally competent, intelligent villain does something stupid like not killing the hero immediately when he has the chance, and that allows the hero to win, that would be an example of PIS (If the villain was just incompetent in general, it would be CIS, or short for "Character-Induced Stupidity" instead).

Examples of PIS

 * Hulk being defeated by Captain America, and an ordinary python, or being severely harmed by regular gorillas.
 * Thor being knocked unconscious by an ordinary gunshot.
 * Superboy-Prime being able to harm Mister Mxyzptlk, and being defeated himself by the Teen Titans.
 * Dormammu being harmed by Cyclops, and defeated by Illyana Rasputina, or Frankenstein's Monster.
 * Spiderman beating Firelord.
 * Arceus losing its Plates and nearly dying after stopping a meteor.
 * Bill Cipher being defeated by a memory wipe.
 * Black Panther subduing the Silver Surfer.
 * She-Hulk almost being killed by a very small explosion.