The act of repeating the same action which proves ineffective the first 2 times it occurs.
To act on the pretense that repetitive actions will provide a solution rather than finding a more effective way.
Ramming your body against a wall instead of walking around it.
Repeatably trying the same button combination in a game that has already proven to not be the answer.
IE: "Johnny cuts himself when preparing food tonight because he is using the knife wrong. Johnny on average cuts himself 5 times a month. Johnny's ignorance makes his way of chopping up food very hazardous to his health."