Jonas, the main character, is elected to become the Receiver, who receives all of the memories, so no one else has to have the memories. Nobody is better than anyone else in the community, except for the Elders . That is why the book represents sameness. It also shows a lesson of what would happen if a community was all the same. When Jonas receives all the memories from the Giver, he realizes how good life was in the past, and how his community is not perfect.
Nobody knows what they lost.
So he wants to change the community.