A phrase used to indicate when a person is at fault or had made some sort of mistake. Can be used in a similar manner as "that's what she said" at the end of the persons' sentence.
Leaving the mall after a long day of shopping for a friends birthday present

Jake: Dude, so what did you buy?
Adam: I bought some shirts, jeans, and a fresh pair of kicks.
Jake: So which one of those is the gift?
Adam: ....gift?

Jake: And that is why you fail...
by AllEyzeOnE March 11, 2010
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Usually added at the end of a praise to make someone feel even worse when you put them down.
22:43 - Kon: Aren't you happy that I gave you it? :(
22:43 - Krabman: Yes! :D
22:43 - Kon: XD
22:43 - Krabman: Just kidding. You fail.
by NatsukiKonaKon January 16, 2010
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