a person with a high failure percentage
a rejected plan of action
1 "Did you find a dress yet?
2 "I went shopping last night, What a Fail Mish! I'm fucked!"
1 "Look at John, he is about to go hit on that hottie"
2 "What a fail mission. No Chance."
1 "Lets go to Tijuana to score a pound of Meth!"
2 "That is the biggest fail mission ever, I'm in."