... knowl-edge is the foundation of sales success. To sell well, the theory goes, salespeople need to develop a detailed knowl-edge of their product, their markets, and their customers.It’s a useful theory, ... the architect of a consistently success-ful life. Consistently successful people are at the MASTERING THE ESSENTIALS OF SALES 58 SUCCESS PRINCIPLEIn the universe of success, there areshooting ... rateamong officers. In corporate America, the best sales managers are not the ones who hide behind theirdesks, but those who go out to see the toughest cus- MASTERING THE ESSENTIALS OF SALES 54...