I was in sales for 20 years before the company took a nose-dive from 30,000 feet. My territories changed over time. The company still had customers, in another territory, that would only deal with me. I built relationships. I got to know my people, their lives, and wishes. I still had people calling me on my cell 2 years after I had left. That company finally tanked 5 years after I left.
The point is, a sales associate is dealing with people. People have wants, needs, desires, and built in prejudices. Learn 'em, and use 'em.