Lack of male role models?  No one to inculcate a work ethic?  

If you are Lamont in NE Portland and you have to dodge Crips and Bloods going to and from school and two of your friends have been beat up because they wouldn't join a gang and you see the dudes with the flashy Beemers and the flashier women in the 'hood are selling drugs or women and you aren't likely to earn a scholarship to go to college, what do you do?