Lowry's society in The Giver is based on the premise that only the best and the brightest should be allowed to live and reap the benefits of living. To this end, the rules of the society are not to permit the aged to live too long and not to allow the infirm to live at all. It's cruel. The value of life in the story is limited to those who follow the rules but who also can maintain their own health in the best possible way. Therefore, as children are born, the Nurturers must test the babies on two main standards: whether they gain weight at a healthy level and if they can sleep through the night by a certain age in their development. If these two goals aren't met, then a committee votes for those who don't develop in these main ways to be released--or euthanized. Gabriel did not meet the standard for sleeping through the night so he was declared to be released and not introduced to a family unit at the Naming Ceremony in December.