Here's an example of how two salespeople (let's call them Kim and Jack) from the same company calling on the same types of customers can have such different selling experiences. One has highly profitable sales, the other does not. And it comes down to their pricing, which is at opposite ends of the spectrum.
Kim's projects nearly always come in on the low end of the range. She typically quotes far less planning time, travel and implementation costs than her projects actually require. She's concerned about her prospects' budgets and feels squeamish asking for so much money. Her clients are always asking her to reduce her costs.
On the other hand, Jack's projects are usually the highest priced in the company. He has no qualms asking for what he feels is a reasonable fee for what needs to get done. And he often pads the budget a bit to cover requests that might expand a project's scope. His clients never blink when they see the price.
So why is there such a difference in these two experiences? Kim truly doesn't understand the business value of her work. She just knows it costs a whole lot for her services and wants to be a worthy steward of her clients' budgets.