qnli question: Why does Sowell believe that there is little to no incentive for the preferred minority groups to perform at their best? sentence: Sowell writes that affirmative action policies encourage non-preferred groups to designate themselves as members of preferred groups [i.e., primary beneficiaries of affirmative action] to take advantage of group preference policies; that they tend to benefit primarily the most fortunate among the preferred group (e.g., upper and middle class blacks), often to the detriment of the least fortunate among the non-preferred groups (e.g., poor white or Asian); that they reduce the incentives of both the preferred and non-preferred to perform at their best – the former because doing so is unnecessary and the latter because it can prove futile – thereby resulting in net losses for society as a whole; and that they engender animosity toward preferred groups as well.:115–147