Incentives vs fiduciary duty

A snippet from Identity Economics, which is in my 'to read' pile:

"The more a CEO's compensation is based on stock options... the greater the incentive to maximise the price at which to cash in. There are at least two ways to do this: one is by increasing the firm's true value; another is by creatively managing the firm's books. recent evidence shows that executives have understood and embraced the second possibility. What can identity economics say about this state of affairs? In our mode, and following Weber, the most important consideration in incentives for executives could be their role as fiduciary. Office holders should fulfill the duties of their office. If jobholders have only monetary rewards and only economic goals, they will game the system insofar as they can get away with it."