If schools are failing to teach children basic skills by the time they are 16 it makes no sense to make them stay at school for an extra two years. If the children are forced to sit in the classroom for longer it does not necessarily mean that the results of education will change. Forcing young people to remain in school against their wishes is a reinforcement of the failure of the educational system. If climbing a mountain on your hands and knees is not working then simply doing it for longer makes no difference. The same is true of education: there is no point in keeping students who are failing in schools for longer periods when there is no evidence to show that they will succeed, instead something new needs to be tried.