Sam Walton has said many times that excellent customer service is what differentiates us from all other companies. He said: "to provide customers what they need to and a little more services, to let them know that you value them. In mistakes, don't look for any excuse and should apologize to the customer. Whatever you do, you should yield three points. I have been in the first piece of wal-mart signs wrote down the four most important words guarantee satisfaction."