Cats have a natural instinct to seek out confined spaces as it gives them a sense of security and control over their environment. Boxes, baskets, and other small spaces provide cats with a cozy and safe haven where they can observe their surroundings without feeling vulnerable. Additionally, cats find comfort in being surrounded by objects that hold their scent, making enclosed spaces like shoes or bowls desirable. It's a common behavior among cats and often portrayed humorously in internet memes, with the phrase "If it fits, I sits" capturing their affinity for snug spots.