Although whimsical hiring violates formal equality of opportunity just as much as discrimination against some applicants done because the applicant is a member of a socially disfavored group, the latter is evidently a more serious violation of formal equality of opportunity.  Whereas being the object of discrimination because one belongs to a group that has been targeted for oppressive treatment in the past is likely to be a wound to one's sense of dignity and self-respect, being the victim of whimsical or idiosyncratic hiring practices is less likely to inflict a significant psychic wound over and above the loss of the job itself. Also, since whimsical discrimination is idiosyncratic, it will not lead to cumulative harm by causing anyone to be the object of economic discrimination time after time (unless whimsical hiring were common and one were extremely unlucky). Also, in the context of a competitive market, there is the pressure of market competition that punishes whimsical economic decisions that lead to subpar economic performance, so one expects whimsy to be a marginal economic phenomenon.