Motivation or Self-fulfilling Prophecy?

I have to start keeping a digital camera with me at all times. I'd use my cell phone camera but it's pretty crappy and I'm pretty inept with it.

Yesterday I was at a car dealership and noticed a whiteboard behind the counter where all the "deals" are approved. It looked something like this: (names changed to protect the innocent)

Dan XXX
Sue X
Bill XX
Bob XXXXXXXXXXXXXXXXX
Jim X
Carol XXXXXXXX
Brian X
Dave X
Sid XXXXXXXXXXXXXXXX

Clearly, this chart was showing each salesperson's productivity for the month.

And it got me thinking.....

If I were the dealer's general manager, what would happen if I let every salesperson go, except Bob, Carol and Sid?

I wonder whether Bob, Carol or Sid have any incentives to share their secrets with the rest of the staff?

What's the reasoning behind posting the sales results in such a public place? If the management is trying to motivate their poor performers, they'd better understand that they're also sending silent signals to their customers as well.

As a customer, would you rather deal with a high performer or a low performer?

Is the chart a self-fulfilling prophecy?