Cats love sitting in boxes because it fulfills their instinctive need to find a protected hiding spot in the wild. Cats like to observe their environment while remaining unseen themselves. Boxes, other containers and close spaces make attractive hiding places for cats.
The lives of domestic cats are filled with other examples of instinctive behaviors. When cats play by stalking, chasing and pouncing, they are practicing survival skills they need in the wild. Cats sometimes sit quietly and attack suddenly. This copies the patient, waiting behavior wild cats display when waiting for prey to come closer. Also, cats who tear into toys are imitating killing prey.