Quality is achieved only by validating customer requirements, through giving them the outcome that they desire. To learn if you are providing your customer with their desired outcome, you must look beyond the bottom line. You must ask them. Customer feedback comes way too late in the process. If you've already produced something bad, that a customer was dissatisfied with, you may have already lost that customer and his friends.
Feedback is in the wrong part of the loop.
Make customer input your guide throughout your processes. Many a leader has focused on a diminishing profit margin only to sell out, or close the doors permanently. To avoid disaster, bring the customer to work with you. Of course, if you want to be an industry leader, you must recognize customer input as only one part of your design and modification processes. It is you, who knows the most about your business.