aight fellas, if you gotta clean out your bum, just buy a douche bulb.
having strong jets of water may fill up your rectum real quick, but 1. it's hard to control how much water is being used, 2. the pressure may damage your insides, and 3. you're also introducing air into you which will just cause a bloated feeling and farts.
your rectum doesn't have much volume, so being able to control how much water you use ensures less water goes up your intestines and therefore less discomfort and oopsie dookies on daddy's dick.