Why do cats hate water? This is actually a myth: Not all cats hate water. In fact, some love it!
It all depends on experiences. Cats that have had positive experiences with water will probably enjoy it in the future. However, any negative experience will cause fear and aversion.
Cats are usually such self-sufficient groomers that bathing isn't necessary. Therefore, they don't get used to the bathing process as young animals. A running faucet can be scary if you've never been exposed to it.
Also, some cats have a thick coat and fine bone structure. A wet, thick coat can weigh them down if they attempt to swim, creating a scary experience. For that reason, some cats really don't appreciate being drenched in a tub.
Veterinarians usually recommend drinking fountains, as most cats prefer running water to stagnant bowl water. Some cats are fascinated by water and can't resist a good fountain. Try it with your kitty!