is when a character does something stupid to further the plot.
is when the plot depends on a character failing to act.
That is the main distinction.
An example of Idiot Ball
would be sticking your finger into a light socket. Or licking a frozen pole.
An example of Plot-Induced Stupidity
would be a hero not activating his superpowers during a fight against a homicidal villain. Or just standing around fretting while a villain destroys the city.
edited 20th Sep '10 6:28:23 PM by Zeta