Of course, a reasonable person would foresee that maybe drinking a couple of beers just before descent might make for problem when the seat belt sign comes on. A reasonable intelligent person would pace their bathroom breaks and liquid intake to accomodate the safety of others.
Of course, also, the world is full of selfish, self-important morons that think that they don't need to think and that if they endanger others with their stupidity, it's not their fault.
My favorite was one day when the aircraft was taxing in, some fat bastard gets up to get a jump on the rest of the pax getting his stuff from the overhead bin. I told him to sit-down until the captain turns off the seat belt sign. He just sneared at me at just about the time the captain had to slam on the brakes. Mr. Fat Bastard goes flying onto the aisle floor.