Basic concept of juvenile delinquency

“I told you that 'juvenile delinquent' is a contradiction in terms. 'Delinquent' means 'failing in duty.' But duty is an adult virtue—indeed a juvenile becomes an adult when, and only when, he acquires a knowledge of duty and embraces it as dearer than the self-love he was born with. There never was, there cannot be a 'juvenile delinquent.' But for every juvenile criminal there are always one or more adult delinquents—people of mature years who either do not know their duty, or who, knowing it, fail.” ― Robert A. Heinlein, Starship Troopers