The author concludes that, when hiring sales reps, we should favor applicants who have engineering degrees but little/no sales experience over applicants with lots of sales experiences but no engineering degrees. This is based on the fact that most of the company’s best sales representatives had an engineering degree but little/no sales experience when joining the company.

The author assumes that the explanation for why most of the best sales representatives have an engineering degree and little/no sales experience is that this background contributes to success. But this overlooks the possibility that there are other explanations. For example, what if most people hired for a position as a sales representative have the background described? Then we’d expect most of the best reps to have that background.