This just had me thinking if there's a relation between your shower habit and your MBTI type. If I had to guess, I'd say there is.
So, what's your MBTI type, how long do you usually shower if you aren't on a timetable and you are alone in the shower and why do you believe you do this.
INTP - thirty minutes to one and a half hour.
I find the sterile environment and dropping of water very stimulating for my Ti-ness.