According to the "Pareto principle", 80% of the effects come from 20% of the causes. This can also be the case for ecommerce, where business leaders often find out that 80% of their profits come from 20% of their customers. In order to assure their profitability, these merchants just have to ensure that 20% continue to buy from their shop. In this guest article, Internet psychologist Graham Jones
presents advice on how to keep loyal customers.