Feeling mindless can be a way to take a break from everyday life. Instead of worrying about stressors, you just let go and let your mind go blank.
If you spend a lot of the day in a state of focus, effort, or just working hard at something that is mentally demanding, being mindless can be a way to re-balance.
For people who are prone to overthinking, being mindless is also a way out of overthinking.
There is no need to analyze why you are wetting your pants, or why you like it.
There is no need to be aware of what you're doing or have a reaction to it.
All you have to do is accept the mindless state and whatever happens, happens.
How do you feel about being mindless? Is this something you enjoy? Or do you prefer being completely aware of what is happening as you wet yourself?