The book uses a good example when referring to mergers. A merger in the future of a corporation could be viewed as a positive move - bringing more wealth, more talent and/or a larger consumer base. However, management could see the move as a negative one as they would have to possibly change roles and give up certain privledges they are accustomed to. Although the merger may bring the corporation positive growth, management could be reluctant to make the merge. This could be the case in a main goal of personal profit maximization. Without the merge, the company could lose steam and competitiveness and shareholder could lose in the end.
It is important to note that shareholders may be employees of the firm who would become more loyal and efficient when they are rewarded financially. Shareholders financially invest in the corporation and if rewarded with good returns, will continue to invest generously. The more shareholders find value in a given corporation, the more likely they are to financially invest, which in turn gives the corporation more positive funds to grow business.
Also, social responsibility may play a part in the maximization of shareholder wealth. If the public perceives a corporation as being socially responsible they may become more loyal customers. Knowing that a local corporation has taken steps toward pollution control would make me much more likely