现代营销理论把一个整体产品分成三个层次,即核心产品（核心价值、利益）、实体产品（产品实物）和外延产品（附加利益和服务）。随着产品同质化现象的出现,买卖双方越来越把自己的关注点指向产品的外延部分,即更加注重给顾客带来的全方位服务。满意的服务可以大大降低企业维系顾客的成本,同时一个满意的老顾客就是企业的一个义务推销员,满意的老顾客又代表着更多的营销机会。 Modern marketing theory divides a whole product into three levels: core product (core value, benefit), physical product (product product) and epitaxial product (additional benefit and service). With the emergence of the phenomenon of product homogeneity, buyers and sellers more and more point their focus on the extension of the product, that is, pay more attention to bring customers a full range of services. Satisfactory service can greatly reduce the cost of maintaining the customer, while a satisfied customer is an obligatory salesman of the enterprise. Satisfied customers also represent more marketing opportunities.