Mostly filled by incompetent myopic administrators (former failures as classroom teachers) who only worry about data and looking good in front of the "region" (i.e., their direct supervisors). Superintendent Alberto M. Carvalho is more interested in looking good in front of cameras (often going around with his personal photographer) and wastes funds for a personal security detail when he visits schools (I guess he needs "secret service" protection...perhaps he's training for one of the white-houses). Sometimes he gives the impression of forgetting that the Estado Novo is gone.
The myopia of the the School Board and Superintendent Office miss two vital variables to success
1) Poor administrators who only think about their own interests and do not value human capital.
2) Accountability should not only be placed on teachers but on students too.
Salaries are also too low, while benefits are an embarrassment. The starting salary is around $41,000/year and you can add an additional $6,000-$7,000 if you have Masters, Specialist, and Doctorate degrees.
Health insurance is free for employees. But if you add a spouse/partner then you pay about $500/month. While if you add children your monthly contributions go up to about $800-$850. In other words you work to pay your health insurance.
Being the 4th largest district in the country it fails to take care of its teachers, hence failing to retain good teacher.