Because swimming is not a "fun" thing for a ball python. Ball pythons are shy reclusive animals that are very easily stressed. Throwing them in a large cold porcelin bathtub filled with water (not matter how "FUN" you think it would be) would scare the cr@p out of me if I were a ball python.

In the wild a ball python would be very vulnerable to predators in a large body of deep water and would avoid it as much as it could. Those instincts are still there in your CB/CH animal. Reasonable people could easily conclude that they don't "enjoy" swimming.

I posted those smileys because when I initially read the post my thoughts weren't exactly "politically correct". 8)

-adam