As university employees, professors have a fiduciary obligation to act in their employer's best interests. The number one interest of a university is financial survival, and the key to survival is reputation, because reputation attracts students, faculty, and donors.
A university's reputation, to the extent that it is at all malleable, can be enhanced by serving students well, and by moving up various university rankings. These rankings are, in turn, driven by metrics such as student/faculty ratios, research funding, journal publications, citations of journal articles, and - because this is all somewhat circular - reputation.
University professors, as a rule, work hard. But some of this work aligns more closely with the employer's interests than others.