When it comes to diversifying the faculty, one of the common arguments is that departments must choose between excellence and underrepresented minorities. As a powerful column by a university provost makes the case that this a false choice.
Yes, there are a limited number of open faculty positions and so offering a job to one person requires shutting out another. But diversity should not be a consideration solely at the point of hiring. Concern for attracting a broad applicant pool needs to begin before the job description is even posted. It needs to come into play when considering where to advertise, how to train search committees on unconscious bias, and how to interview candidates.
Then, once the most representative pool of candidates is assembled, departments should hire the best person for the position. Achieving diversity is not desirable for its own sake. Rather, it advances the educational mission of any university.