Businesses that truly deliver outstanding service are perceived as adding value to the product or service in some way. Value is also added by the quality of the product or service involved. Products and services that are perceived as being of high quality and reliability are usually thought of as providing value. If the gap is too wide, sales will suffer. It is important to focus on ways to enhance value for your customers.
Customers are fickle and their situations change.
Those two factors alone should be enough to make any business that relies on one or a few customers to be nervous. It is important to expand the customer base so that sales are spread across a relatively large number of customers. By doing so the risk of business failure due to customer leakage is reduced dramatically. We often refer to this as risk dilution. Look at your own customer base.