Why the community can not afford a failure with the receiver of memory

The Chief Elder explains that the community only has one Receiver, who will train Jonas personally. Jonas sees that she watches one of the men on the Committee of Elders, who has pale eyes and who seems separate from the other Elders. The Chief Elder also explains that ten years ago, the previous selection of a Receiver failed, so they have selected Jonas with great care because they cannot afford a second failure. The Giver must be able to pass on all of his knowledge before he can no longer do so.