Why do most cats hate water?

The main practical reason is the coat. Cat fur absorbs water rather than repelling it the way a duck's oiled feathers or an otter's dense underfur do, so a soaked cat carries significant extra weight, loses body heat rapidly, and takes a long time to dry. For an animal whose survival strategy depends on agility and quick escape, being waterlogged is a serious vulnerability. Domestic cats also descend from wildcats of arid regions in the Middle East and North Africa, where deep water was rare and there was no evolutionary pressure to become comfortable in it.

Early experience matters as much as instinct. Kittens exposed to water gently during their socialization window often tolerate or enjoy it, while cats that first meet water in an adult bath are learning about it under maximum stress. Several breeds contradict the rule entirely: Turkish Vans have a water-resistant coat and a reputation for swimming, and Bengals, Maine Coons, and Abyssinians frequently play with running water. That is also why so many cats are fascinated by a dripping faucet while hating the tub, moving water is interesting and possibly reads as fresher than still water, but immersion is the threat. Most cats do not need bathing at all, since grooming handles it, and the exceptions are medical or for long-haired cats who cannot keep up.