It is an agreement that allows a person to remain on the land or in the propery for the term of their life while, at the same time, you own the property during their occupancy. I am a REALTOR.
We rotate ours each month. Then after four rotations we switch sides for another four rotations then repeat. After a while it becomes a habit. At first I had issues not sleeping "on my side of the bed". But I realized I began to sleep better, and less back pain.
It depends on what its made of - my mattress is foam with gel, and I don't have to rotate it.
