As listing agent I spend more on marketing luxury homes than median-price homes but that is about the product not the compensation. However I couldn't spend as much if the compensation was identical (flat rate rather than %).

My job is to help people to buy and sell homes.  Not to make a sale just for the $$$$ .   

I have 5 LO's, they all make a lot of money, many companies attempt to hire them and no one is planning on leaving.

I work the same for every buyer, regardless of the purchase price or the compensation payout.   Maybe I am old school, but I dont charge the buyers if or when it does not pay the full commission (usually short sales, REO, or limited/flat price listings).  I even tell them the properties that dont pay out the full %, so they know.  The reason why?  By the time buyers are ready to make an offer, there is a lot of trust.  Many times they want my opinion on properties, location, etc.  I wouldnt want them to think what I got paid impacted that advice (it doesnt).  Good question.

I agree with Barbara Todaro. I don't think commission affect one's sales performance. 

commission has no impact on our sales performance.... none....

The compenstion is the incentive to make the transaction happen. 

Decades of research has proven giving someone a raise does not lead to better performance. What one agrees to work for often does lead to disappointment when the realization they devalued themselves surfaces.

Performance is better manipulated by focusing goals on those things that LEAD to compensation, but not the compensation itself.

Such as, "Let us work together to implement your "GLN" plan, as defined, and work towards setting a record of 10 listing appointments for you this month."

Probably positively.

Good answers here.

Directly!