Today, customers have a choice. Most markets have several competitors. For a variety of reasons customers can leave at any time, especially those who have had a bad or even slightly disappointing customer experience. The solution is to identify dissatisfied customers and take care of them before they leave the company and turn to the competition. This care must take into account the key points of the customer experience, which are personalization, good support, transparency of information (readability, completeness) and immediacy of customer service (accessibility, immediacy). One of the major challenges for companies is therefore customer satisfaction; no company will tell you that customer satisfaction is not one of its concerns. But, in the end, why is it so important to measure customer satisfaction and to try to improve it? Customer satisfaction is a competitive advantage because it allows us to differentiate ourselves from our competitors. For an equivalent product or service, customer satisfaction can tip the balance in the eyes of a prospect.