Usually because they "know" somebody or because somebody "owes" them. It's really a case by case situation. The Summers kid was probably made an Assistant Director because that is appointed, therefore, they don't HAVE qualifications. Look at when Dossett was made the Assistant Director of DJJ - when he wasn't legally qualified to hold almost any position there - they have to bring them in at a level that avoids those nasty little complications like qualifications.