Hoarding is the excessive accumulation of items and the inability to dispose of them. This results in the individual's space becoming filled to capacity and a decrease in their functional living area or space. Most people have the capability to discard these items after they no longer have a use for them.
But hoarding goes beyond simple clutter. In the homes of compulsive hoarders, you may find items stacked on every surface of their home. The person will devise pathways to maneuver around the accumulated clutter, and, in excessive cases, the actual living space is minimal with "treasures" stacked from floor to ceiling..." More