Clean living conditions, clean neighborhood act as good living conditions and keeps the dwellers in a pleasant mood in general. It also adds to one's good habits, helps keeping good health and gives good impression. Maintaining cleanliness does take a little extra effort but its worth it.
But as for everything, obsession spoils. A person obsessed with cleanliness can't and won't tolerate anything otherwise. Sometimes it does get difficult to stay in presence of such a person. The obsession with cleanliness takes away the goodliness factor.
Interestingly when I start cleaning up my room I enjoy it. Its quite a recreational activity, sweeping, cleaning up the cob webs from all the corners of the room, collecting empty packets and wrappers from under the table and under the bed etc.
Easiest and most convenient, which apparently looks inconvenient, way is to always keep things at their properly assigned place. A well organized space (in this case, a room) has maximum chances of remaining clean. A rack for clothes, for shoes, for books, a dustbin for garbage etc.
Making one's bed after waking up is a good habit and adds to cleanliness and goodliness.
Before arrival of guests, people sincerely tidy their room, spray perfume/deo in the air, spread clean bedsheet and maybe stuff the closets and cupboard with things, assign kids responsibility of tidying up their respective rooms etc.
P.S. - My mother cleaned up my room when she visited me this week in college... felt ashamed of myself. :(