While Katy has served some awful performances worthy of the title of "worst performance by a pop girl," I feel in this case the error was mostly on the show's sound people and not necessarily a lipsync. For better or worse Katy always sings live, and she does in that video a little after the suss it all out.
she did great live, it's just the beginning that they started a lysincing track and she decided to come out and then the person stopped the whole thing
she should have stayed inside waiting for someone stopping the track, it ruined an otherwise good performance
She wasn't lipping though, her mic was off. Not ha fault
