The concept of product phases is related to the economic (or marketing) product life cycle (m-plc). Both consist of six phases. Introducing product phases opens up the possibility to analyze the relationships between the different fields of industrial design: ergonomics, marketing, construction and styling. The styling of a product can be analyzed in relation to its (primary and secondary) functionality, its ergonomic qualities, its production technology and the marketing techniques that are used to sell the product. To demonstrate this, we propose six qualitative product phases - performance, optimization, itemization, segmentation, individualization, and awareness - complementary to the (essentially quantitative) phases of the product life cycle. Placed in chronological order, a more or less general pattern reveals itself, enabling the possibility of explaining and predicting - to some extent - a product's development. Each product phase can be described in product characteristic terms which apply to the product itself: to its market, and to its production technology, the services that accompany the product and the ethical aspects of the product in question.