Dahl continues in these chapters to separate grandfather and grandson in order to make Charlie the only possible canaidate to take over the factory. Just as Grandpa Joe doubts MrWonka's glass elevator, he is skeptical about Mr. Wonka giving Charlie the chocolate factory. Grandpa Joe's skepticism further highlights Charlie as the only one who never lost faith in Mr. Wonka. This final distancing of Grandpa Joe from Charlie solidifies Dahl's contention throughout the novel that children are good and adults are not. Those children who do not seem good are that way because of poor parenting.
Dahl ends the novel by reframing how a child ought to be. Mr. Wonka explains the author's position when he outlines how Charlie is the perfect child to run the factory. Charlie has to be respectful, which he has already established. He also has to be willing to do things exactly as Mr. Wonka wants them done, which his unflagging faith in Mr. Wonka predicts. Finally he needs to have the imagination and love for the factory that will ensure future success. Charlie's acknowledgment that he too loves the factory proves to Mr. Wonka beyond any doubt that Charlie is the one.