Now there's a day to celebrate! Is it only coincidence that it comes the day before Mother's Day? Clean rooms from all my kids would certainly make a nice mother's day present, but I doubt I will get it. My youngest and oldest kids have terminally messy rooms, in spite of all my efforts; entropy wins in their rooms. My middle two prefer to keep their rooms neat (unless I start nagging them, in which case the rooms get substantially messier), so I guess the messiness quotient is genetic more than age-related.
But which chromosome controls whether people like to keep their rooms neat or let them become a complete disaster. Maybe it has to do with bright ideas; if there are dozens of new ideas popping in your head, it is hard to focus on something so mundane as a messy room. On the other hand, I can't think well if the room is too messy; for me, ideas pop when my room is neat. Maybe it has to do with how visual you are; visually-oriented people might be more bothered by the mess. Or big-picture people might not notice the messy details. It can't be a matter of sensory sensitivity; some people I know who go into sensory overload easily are also tolerant of messes. I like to think that it is more practical to have a place for everything and everything in its place, but I have to admit that lots of messy people can find things very easily; they just use a piling system instead of a filing system (and I reluctantly admit that they spend less time keep their system functioning). Maybe it doesn't have to do with any other characteristics and is on a completely separate gene, inexplicable and unpredictable.