i teach kids from 2.5-15yo.
by the time they reach a certain age, children do not need to be escorted to the bathroom, and are well past the potty-training phase.
you would think that allowing an 8yo to take care of themselves in the lavatory was acceptable, right?
one of my students (i'm yet to figure out who) pissed ALL OVER the floor. you could barely get a foot in there.
and when i finished cleaning up all that lovely wee, the floor was sticky. thank god japan uses the toilet slipper rule.