The cat understand perfectly the test, but think that, if you like it so much, leave me alone and do it yourself. A dog is a pack animal and for this reason it obeys, yes or yes, the leader of the pack, the owner, a cat or felines in general, with the exception of lions, they are solitary hunters and do not have the concept of a leader, A cat sees you as an equal, at most a friend, but not as a leader. This has nothing to do with intelligence, but with the very nature of these animals.