Extrinsic motivators narrow the focus. That’s why they can be effective, because they make us concentrate and directed. But this narrowed focus comes at a cost: complex or conceptual tasks can narrow the holistic thinking that is necessary to come up with creative and innovative thinking to solve a problem. If you reward a student in a learning situation with an extrinsic reward, the student will learn only as much as is needed to beat the test, but likely not try to thoroughly understand the topic.
As Dan Pink concludes in his book Drive: The Surprising Truth About What Motivates Us, carrots and sticks have what he calls The Seven Deadly Flaws. They can
- extinguish intrinsic motivation.
- diminish performance.
- crush creativity.
- crowd out good behavior.
- encourage cheating, shortcuts, and unethical behavior.
- become addictive.
- foster short-term thinking
The opposite are intrinsic motivators.