You have more customers than you know. To begin with, your employer is your primarily customers that you have business with. And your most essential work is to satisfy your employer by doing whatever in your capacities to what he or she considers to be most essential tasks given to you at an particular period of time.
Also apply to you, if you a manager of an organization or business entity, your staff also serve as your customers. Your jobs is to satisfy them so that they can do outstanding job in satisfying people who they are meant to serve or who patronise them. if you're in entrepreneurship or sales, those in the marketplace who patronise or use your product or service are perchance your most valuable and essential customers.
All The great success of yours, great fortune coming from satisfying and serving people with what they are in need of, and willing to pay the price of it, better than somebody else can serve them.