You don't hear much about zero-defect companies anymore. Maybe that's because people have finally figured out there aren't any in existence. As I've traveled down the corporate road I've wondered from time to time how flawed people in a very flawed world are supposed to achieve perfection in anything. It's pretty ludicrous, when you think about it.
Early in my career I worked for a company that got all excited about achieving zero defects in our processes. In my youthful exuberance I was one of the people leading the charge. We really tried to eliminate all unfilled orders and any mistakes in how work was handled. It was a worthy aspiration. But after visiting offices where I found unfilled orders that were never recorded and were then conveniently filed in the trash I made an enlightening discovery. Zero defect cultures don't result in the absence of defects as much as they generate sophisticated ways to hide defects so they go unnoticed (and therefore unpunished).
Even with the best efforts to anticipate and plan for problems, some mistakes will occur. Realistic customers understand that and if you have a proactive method for fixing problems when they happen--you can usually keep a customer.
One of the fastest ways to promote dishonesty in an organization is to bridle people with unrealistic expectations.