Sometimes when you're in an MMA fight and things are looking dicey, you try to pull out all stops. In these specific cases of self-inflicted knockouts, these fighters may have done a little bit too much.
Take a look and see for yourself:
I've watched this video a few times and it never gets old. These examples are like the "own goal" from soccer, except for MMA. It's brutal and devastating, but you only have yourself to blame, really.