What is You Fail It?
1.
A term that could be used as an insult or to take the piss when someone makes a silly mistake (a bit like 'duh' or similar) or fails something (like a test or challenge).
Originates from a game called 'Blazing Star', where the game over message reads: "You fail it! Your skill is not enough, see you next time, bye-bye"
2.
-It's not for you
-You don't get the prize
-This ain't you farthers saiyuki
All in all, you got served and you most certainly fail it
"Why Mr Darcy, are you trying to insinuate that my womanhood can be given away at the toss of a hat, i do belive that you fail it"