If your cat brings dead birds or mice to you, then you might wonder why. The scientific reason is that cats are hunters who have not been fully domesticated. The real reason is that cats like to see your reaction to dead animals just to freak you out and get away with it.
To avoid hurting your cat’s feeling, it’s best to praise your cat for its dead offering, then dispose of it right away. Of course, once you please your cat with praise, it will likely rush right out and get you another dead animal, thinking it’s something you like and enjoy.