What is the marketing concept and how does relationship-building support it?

"Marketing includes those business activities that are designed to satisfy consumer needs and wants through the exchange process. Marketing managers use the “right” principle—getting the right goods or services to the right people at the right place, time, and price, using the right promotional techniques. Today, many firms have adopted the marketing concept. The marketing concept involves identifying consumer needs and wants and then producing products (which can be goods, services, or ideas) that will satisfy them while making a profit. Relationship marketing entails forging long-term relationships with customers, which can lead to repeat sales, reduced costs, and stable relationships."