Shes not a typically great dancer from a pop star perspective. When she does her own thing it fits her, even though some people here talk **** because its not like a choregraphed routine (ARTPOP on Fallon for example, people were like wtf is she doing). Shes not really a choreographed artist so when she has to go that route for tours or some performances it can at times look awkward.
Only pop girls can actually dance are Madonna, Janet Jackson, Rihanna and old Britney.
Britney used to be able to pull off sharp choreography however in all actuality (something no one ever seems to talk about on here) she was not very graceful. Her dancing was not fluid. It was very cold and calculated like "heres this move, now here this move, now heres this move" it wasnt like natural. But it fit her whole manufactured aesthetic though.
She's a great dancer but if she dances too well it hurts her singing. I mean, you guys forget that she is singing while dancing. Still, she sometimes chooses to dance sloppily, most likely because she's tired.