As it is now, all that lives dies, but not all that has died comes back into life. Left unchecked, death would eventually win out over life. In physics this is called entropy, and it seems to make sense. It gives everything a chance to change, and creates space for new things to come into manifestation. This is pure hooey.
Death is a limit to life.
When something dies, it ceases to exist in the form of its being, and can not reconstitute itself. The life-force energy and identity are lost, and the physical body disintegrates and returns to its previous fragments. The magnetic essence is torn apart as it's pulled away from the body on one hand, and the escaping spirit essence on the other. And Heart, the sacred place of our meeting, is of course destroyed in the process. There has been too much suffering in Creation as a result of the Asuras' quest for death, disease and other forums destruction.