Cats knock things off tables primarily due to instinct, curiosity, boredom, and learned behavior. As natural predators, cats are hardwired to be attracted to moving objects and may push items to simulate hunting or to see how the object reacts. This behavior is also a way for cats to stimulate themselves when bored or to seek attention from their owners. Additionally, cats may mark their territory by knocking items over, leaving their scent on objects. Owners may unknowingly reinforce this behavior by responding with attention when it happens. Managing a cat's environment, providing toys, and ensuring regular playtime can help reduce this behavior.
