Professor is already a very comfortable job. Adjunct lecturer is an awful job, but the requirements for those are already quite low, and frankly generally don't include "is an effective teacher". IMO, the problem here isn't supply-and-demand for the lecturer job; the problem is that the service being provided ("teaching a course") isn't the product the customer (student) is buying! In the common case, the student is buying a degree and doesn't care about the course (because the course is a "distribution requirement" inside or outside of major, or because the whole major/degree is a a pointless arbitrary requirement put in place by employers). On both sides, student and teacher, parties are simply going through the motions to fulfill the illusion of a meaningful degree.