Every person alive has had to use the restroom. What you mean is that you have a bladder issue.
No bladder issue. Probabilistically, when you load a bus up completely with people (the ideal situation for transit) one of them will have to use the restroom over the course of an hour and a half.
No bladder issue. Probabilistically, when you load a bus up completely with people (the ideal situation for transit) one of them will have to use the restroom over the course of an hour and a half.