When it comes to neatness, my girlfriend is more on the neat-freak end of the spectrum, and I am closer to the border of the People's Republic of Slobistan. And so it puzzles me when she will, for example, look under the couch and say something like, "oh, wow, there is so much dust and cat fur under here!" This is said as if it is something both completely unexpected and deeply disturbing, the way you might say to someone, "dude, what is this dead hobo doing in the trunk of your car?"
To me, of course, under the couch is exactly the sort of place where I would expect to find dust, and the cat fur would be much more shocking and mysterious if we didn't own cats. And neither one especially bothers me, because I don't plan to spend a lot of time under the couch anyway. In fact the whole point of having a couch seems to be to sit on top of it and not beneath it. So to me, it's a bit like saying, "Whoa, what are all these pine needles doing all over this forest?"
But I guess this is the difference between neat-think and slob-think. In neat-think, it is disturbing to realize that an area that hypothetically could be clean is not in fact clean. In slob-think, the default state of things is dirty, so "discovering" that something is dirty is not surprising at all, and the question is whether cleaning it is really necessary.