Anybody can "talk" to customers, but it takes skills to be an effective salesperson. Some of those skills can be learned by trial-and-error while talking to a lot of customers over a long period of time. The problem with this approach is it requires mistakes. (It even has "error" is the name.) Mistakes mean the salesperson has probably lost some sales, and lost sales mean lost income. How much of your income will you continue to put at risk,...