The tainting essence of carrots.

Goals that people set for themselves and that are devoted to attaining mastery are usually healthy. But goals imposed by others -sales targets, quarterly returns, standardized test scores, and so on- can sometimes have dangerous side effects.

Like all extrinsic motivators, goals narrow our focus. That's one reason they can be effective; they concentrate the mind. But as we've seen, a narrowed focus exacts a cost. For complex or conceptual tasks, offering a reward can blinker the wide-ranging thinking necessary to come up with an innovative solution. Likewise, when an extrinsic goal is paramount -particularly a short-term, measurable one whose achievement delivers a big payoff- its presence can restrict our view of the broader dimensions of our behavior. As the cadre of business school professors write, "Substantial evidence demonstrates that in addition to motivating constructive effort, goal setting can induce unethical behavior."

The examples are legion, the researchers note. Sears imposes a sales quota on its auto repair staff -and workers respond by overcharging customers and completing unnecessary repairs. Enron sets lofty revenue goals -and the race to meet them by any means possible catalyzes the company's collapse. Ford is so intent on producing a certain car at a certain weight at a certain price by a certain date that it omits safety checks and unleashes the dangerous Ford Pinto.

The problem with making an extrinsic reward the only destination that matters is that some people will choose the quickest route there, even if it means taking the low road.

Indeed, most of the scandals and misbehavior that have seemed endemic to modern life involve shortcuts. Executives game their quarterly earnings so they can snag a performance bonus. Secondary school counselors doctor student transcripts so their seniors can get into college. Athletes inject themselves with steroids to post better numbers and trigger lucrative performance bonuses.

Contrast that approach with behavior sparked by intrinsic motivation. When the reward is the activity itself -deepening learning, delighting customers, doing one's best- there are no shortcuts. The only route to the destination is the high road. In some sense, it's impossible to act unethically because the person who's disadvantaged isn't a competitor but yourself.