Actually, I had an encounter today that makes a good analogy.
Cell phone employees work on commission. Do you know what that means? If you ask them "What phone do you suggest?", the vast majority will answer with the most expensive phone in the place. They are rewarded for selling an expensive phone, not for satisfying a customer. Now certainly, you may say that a smart employee will realize that over the long-haul turning more customers into sales, even if they are lower sales may net more. But people that smart aren't working at phone stores generally.
The point?
People that smart aren't working as cops.