I think its the background color being a light gray and the model completely black making it look like it's flat and 2D.
In that case I think perhaps this is more of an optical illusion than any sort of brain test and the rest of you just havn't looked very closely. Given perspective it is impossible to view this animation as rotating clockwise.
It works because there is no surface detail to focus on and its a symetrical animation.
I'm starting to wonder if it gave me the same animation as everyone else.
The shadow of her with her back to you is exactly the same as when she is facing you
Her leg is smaller when it is facing away. Once you realise this you realise that not only is there a spoon, but there is a full set of cutlery in my cupboard.