Human resource management is not always or solely the presentation of gifts. Sometimes bad news has to be delivered. We are not thinking here of bad news as in, "You're fired," in which the relationship is ended. Think instead of "You did not get the promotion" or "We will not fund that training in your case." It sometimes helps to be able to layoff at least some of the blame in such instances. Doing so can help preserve cordial relations between a superior and subordinate. In addition, hearing bad news from a third person may help the person getting the bad news to save face, a psychological fact of life that has a lot to do with the persistence of management consulting as an industry.
As for objectivity, it is sadly the case that some general managers are less than paragons of objectivity and virtue. Some are susceptible to corruption, some attend to private agendas, some are prejudiced, and some are simply capricious. To place the administration of human resources practices solely in the hands of such a manager is unlawfully to produce good outcomes. Moreover, to place the administration of human resources practices solely in the hands of a virtuous paragon can lead to (incorrect) feelings of caprice, corruption, prejudice, and so forth. Not all paragons have had the time and track record needed to develop the untarnished reputation that deserve, and an employee who is denied a promotion or rise by a paragon can be forgiven for sometimes confusing his own unhappy exit with managerial discretion exercised unfairly. And when an individual manager is given a lot of authority, even if she is incorruptible, the temptation to try to corrupt her might prove too strong for those who futures she will influence.
Even a line manager who is a veritable paragon of merit and who is recognized as such has a lot of concerns to balance. When some of those concerns involve measures of performance that can be affected quickly (such as product shipping date) and others involve noisier, long-delayed outputs (such as the manager's and firm's reputation with the work), line managers may make compromises that are not in the organization's long-term interests.
Individual line managers may not fully understand or appreciate the organization's human resources strategy and policies, and the long-term reputation sent with employees. This can be a particular problem in settings characterized by relatively high rates of managerial mobility, which can impede stability, consistency, and "memory" as far as human resources management is concerned. Simplicity, consistency, and clarity must be traded off against the complexities of real life.
For all these reasons, human resources experts in particular special areas can play an important role in advising and educating line managers; helping sustain a coherent and consistent human resources philosophy through the organization; and even, in some cases, acting as independent authorities or appealing officers, in case employees feel aggrieved by line management decisions.
In-the-field human resources specialists can also help in evaluating and improving the performance of line managers. It is perhaps difficult to evaluate performance in the area of human resources strategy and policy formation, but even evaluating how well policies are implemented is difficult. General Managers have a lot of things to attend to, and it is therefore expected and natural that human resources will be pushed toward the back burner.
Promoting a culture that elevates the management of human resources, relying on intrinsic motivation of line managers to some extent. But some accountability - some measurement of performance - will support the desired culture. Specialists are likely to have the best training and widest range of evidence for conducting comparative evaluations of human resources performance. Hence, they are well positioned to provide measures of performance on which line manager accountability can be based and to counsel line managers regarding how to improve their effectiveness in formulating and implementing policies for their units.