Looking for some advice on how to best explain / model the following - here is a user story of what I am trying to do:

I manage a sales team who has a bi-weekly goal set and is measured against other sales teams who have a different bi-weekly goal - they are measured and compared on percent to goal. The goals are set based on historical data/performance.

What I am trying to figure out is how to explain:
>That the probability of over-performance compared to goal is more likely with on the team with a lower goal because they have to earn less compared to the team with the higher goal even if the team with the higher goal has more opportunity (one can say if they have more opportunity, the proportion in which they can exceed goal would be equal to the team with the lesser goal, however the production possibilities curve needs to be taken into consideration.)
>All team sell the same products; the differentiating factor is opportunity to sell. My belief is the production possibilities curve comes into effect on the team with the higher goal because it they would need to sell for example 3 $500 dollar things to get the same results the team with a lesser goal and less opportunity would need to do for only like 1 x $500. I don't think that production possibilities support this.

Thanks for the help - I have been trying to argue this point forever. Any help in being able to better understand how to calculate, explain, or model this would be so helpful!!! Let me know of any other info needed.