This is like the trillionth time she get caught lipsyncing, it's not like anybody would be surprised or anything, but she doesn't even bother to take lipsyncing lessons.
Or maybe it's cause she was ready to sing, but the beat wasn't. I find it weird that after that she stared dancing again and her dancers came out and they started back like normal.
Maybe she goofed and thought the song started then. But her backround vocals weren't playing and the same beat was going....