Generally speaking being in a space where things are tidy and orderly is supposed to have a psychological effect, making people more focused, organized, disciplined and so on, so pursuing their important goals more efficiently. I don't think anyone tested it scientifically, it is more like the pop-psychology of it. There is another idea that clutter is cognitively exhausting, perhaps a chaotic looking bed is in this category...

We know militaries tend to be very anal about this (make your bed perfectly, fold your clothes perfectly, and so on...) and they tend to be fairly efficient organizations so it must have some psychological effect probably, but it is not sure it is the kind of psychological effect you would want (obedience training, for example).