What I'm Learning at State College - Diversity over production?

Retiree now adjunct instructor stated he didn’t understand statement in textbook, “Many managers pay too much attention to numbers and not the diversity of their staff”. He claimed to be all for diversity yet felt numbers should be paid closer attention to otherwise a business would go under without profit. He doesn’t understand the statement or the balance suggested. The whole concept of diversity is about hiring a diverse workforce that the public, prospective customers, and prospective clients can relate to. By doing so, profit increases as the public feels the company is a company of them, by them, and for them.