Any property owner or non-owner resident has a responsibility to maintain a safe apartment, building or premises. Any guest or invitee that enters the property has a reasonable expectation for the premises to be safe. It is a right. So when a dangerous condition exists and it isn't properly addressed, you can get a premises liability lawsuit that comes from the accident related to the dangerous condition if someone is harmed.
But who exactly is held responsible when this happens? Who is at fault? The short answer is "it depends."
Some states classify the person who entered the premises and was hurt. They could be a social guest, an invitee, a licensee, or a trespasser. The latter doesn't have any right to sue on the grounds of premises liability since he or she had no right to be there in the first place.
The dangerous condition itself is important, as are the actions of the individual or party responsible for the premises. Did they know about the condition? Were they in the process of addressing the problem? Should they have foreseen an imminent problem?
There is also the factor of comparative fault, where both parties are deemed responsible for the incident: the property manager and the guest or invitee. Even under this circumstance, though, usually one party has to pay the other.
There are plenty of complex factors that go into a premises liability case, and it is best for anyone in this unfortunate predicament to consult with an attorney.
Source: FindLaw, "Premises Liability: Who Is Responsible?," Accessed June 9, 2017