What makes a play ballsy? Does there have to be a miraculous outcome? Does the performer or team have to defy all odds in order to succeed?
The bottom line is that all of these people were not afraid to lose. You cannot win at the biggest stage, if you are not willing to put it all on the line and do whatever it takes to win.
In all likelihood, these plays were the result of an "act now, think later" attitude. They make this list and have secured a spot in the limelight.