I once worked for an architect on a job where we we doing blue prints of a housing project which (unbeknownst to the tenants) was to be torn down and replaced with luxury condos. We had to go through every unit of this building. I have NEVER seen (or imagined) anything like what I saw. Rats, roaches, filth, human waste, all over the apartments. I saw units wherein there were wall-to-wall "mattresses", 8-10 people living in a one bedroom apartment, hypodermic needles all over the hall ways, etc.
The last unit we went into was inhabited by a guy in his late 20s or early 30s...his apartment was immaculately maintained. We asked him about it and he said that when he moved into the building, all of the units were as perfectly maintained as his, but, that since nobody in the building took any pride in their surroundings, they did not bother to maintain their units.
Too many people looking for a handout, not enough people trying to do things for themselves.