Before, during, and after a sale, a selling strategy must focus on meeting a customers needs.
It is important when you are trying to sell a product or service to someone, that they see the benefits themselves. As a sales person your job is to make sure the product you have is meeting the customers needs fully because if they don't see that, they won't make the purchase. As a customer, whenever I buy a product I run down a list of ways it will benefit me or why I need it.