A flat attitude comes from the A Bad Attitude is like a Flat Tire quote. A bad attitude from a person who can't let something go, no matter how long ago or truthful it really is.
Person 1: Taylor Swift's had such a flat attitude in her acceptence speech at the Grammys.
Person 2: Yeah. Wasn't the whole feud between Kanye and her years ago?
Person 2: Yeah. Wasn't the whole feud between Kanye and her years ago?
by AnAverageGrammarNazi February 17, 2016