Quoted: A nationwide trend for universities to use adjunct professors instead of a tenured faculty has become so extreme that some schools are pulling back... Several studies of individual universities have determined that freshmen taught by many part-timers were more likely to drop out.

Quoted: The lack of tenure can leave adjuncts vulnerable. In a number of cases, professors outside the tenure track have been dropped after run-ins with administrators over everything from grading to opinion articles in newspapers.