Because as far as I can tell, all it actually does is what any Zumba Fitness DVD does.
Even if you stand still and don't move AT ALL, it goes green and tells you you're doing well and getting moves correct......??
It's not my Kinect sensor before the inevitable comments start. Dance Central works PERFECTLY minutes after playing Zumba.
Utter garbage. Seriously, how do they get away with releasing stuff like this?