Shareholder speculation corrupting management.

Roger Martin argues that speculators act to distract management from their task,

At the very heart of the problem are two deeply flawed theories — first, that the obligation of management is to earn a return on the expectations of shareholders, however insanely high those expectations happen to be: and second, that stock-based compensation provides a useful motivation for management to take care of their company. They both sound good on the surface, but shareholders would be better off in the long-run if management felt the obligation to earn a fair, risk-adjusted return on the investment capital they were given and if their performance incentives were based on their company’s performance in the real game.