Security systems, alone, are not sufficient deterrents for crimes against people and property although some components, such as cameras and electronic access control can help reconstruct what occurred, after the fact. When organizations considerer upgrading their security systems, they should also objectively assess their policies and procedures, staff training and systems maintenance. For example, an expensive camera is of little use if the lens becomes obscured or misaligned and no one corrects it; an electronic access control device is of little use if no one checks when a door is propped open.