To explain this, let's start off small. Consider a restaurant. We have a cashier, waiters, busboys, and cooks. (Yes, yes, they can be of either sex.)

No one cares about the cashier unless the pay line is moving too slowly. If it's moving too slowly, we can either get him help, or ask him to speed up. If he speeds up, and the pay line movement is acceptable, he won't get help.

But, maybe, he is having to put forth an extraordinary effort to make this happen. If he were to slow down just a little, he might have gotten help. Thus, he is being penalized for doing a good job. But, if he works too slowly, he'll get fired. So, he has to do "just enough" to get by. That's an excellent working definition of "mediocrity."

Now, look at the waiter. The more tables he has, the more tip opportunities he will have. But, with more tables, the worse service each table will get. Thus, each tip will be smaller. So, if the waiter is concerned about giving good service to his customers, and demands fewer tables, he will make less money.

If a busboy is good, he clears the tables quickly. That way, there is more throughput. This means more customers in the restaurant. And, with more customers, there are more tips to be shared with the waiter. OK. But what if one of the waiters is getting lower than average tips since his level of service is worse than the others? Now, the busboy assigned to this waiter's tables is making less money, literally through no fault of his own.

By the same token, assume that a terrible busboy is assigned to the tables of a crackerjack waiter. He, too, is being compensated through no fault of his own, although he is making more money, in this case. In justice, though, we feel that we cannot impose too much of a performance standard on a "lowly" busboy. I mean, it IS an entry-level unskilled job. How long is a busboy with initiative going to stay a busboy??

What about the cooks? If their performance is judged on speed, read what I had to say about the cashier. If their performance is judged on quality, the reward is dubious.

Quality food takes longer to prepare, so the waiters and busboys will be upset since there will be fewer customers per unit time. If a large tip is given based on the quality of the food, do you think that the waiter will share it with the cook? As it is, the better food took longer to prepare, and the waiter served fewer customers, thus making less in tips, overall.

Are you depressed yet??