You have states like Florida that have completely abused the statutes making it easy for teachers' licenses to be revoked if they have two "unsatisfactory" evaluations and having absolutely nothing to do with real misconduct. A teacher can make a fresh start elsewhere if terminated, but not if that license is revoked.
Administrators very rarely have their licenses sanctioned at all. Even in states like Oregon with "tough" standards, meaning the state often sanctions teachers for petty or downright stupid reasons, administrators are more often given a slap on the wrist than are teachers.
From the article:
Over the course of a year, the USA TODAY NETWORK gathered the databases of certified teachers and disciplined teachers using the open records laws of each of the 50 states. Additionally, journalists used state open records laws to obtain a private nationwide discipline database that many states use to background teachers. The computerized analysis of the combined millions of records from all 50 states revealed:
States fail to report the names of thousands of disciplined teachers to a privately run database that is the nation’s only centralized system for tracking teacher discipline, many of which were acknowledged by several states’ education officials and the database’s non-profit operator. Without entries in the database, troubled and dangerous teachers can move to new states — and get back in classrooms — undetected.
The names of at least 9,000 educators disciplined by state officials are missing from a clearinghouse operated by the non-profit National Association of State Directors of Teacher Education and Certification. At least 1,400 of those teachers’ licenses had been permanently revoked, including at least 200 revocations prompted by allegations of sexual or physical abuse,
State systems to check backgrounds of teachers are rife with inconsistencies, leading to dozens of cases in which state education officials found out about a person’s criminal conviction only after a teacher was hired by a district and already in the classroom. Eleven states don’t comprehensively check teachers' work and criminal backgrounds before issuing licenses, leaving that work to local districts — where critics say checks can be done poorly or skipped.
Of course dangerous teachers need to be screened out beforehand, but given how political districts are, teachers with fewer problems are going to be fucked over because some states take their licenses away if they run afoul of an administrator.
And there were always be a few who fall through the cracks because almost all teacher misconduct involve first offenses. There is no way to screen them out beforehand.