Quality is usually considered to be an attribute of an object, its degree of excellence or, more subjectively, fitness for use. Stemming from this point of view, the goal of most ranking systems is to find efficient ways of discovering, or rather uncovering, the quality of specific products or services. However, from a social psychological perspective it seems that the notion of quality belongs predominantly to the realm of social relationships. We argue that quality exists mainly between the users of an object, not within the object itself, and its functions are predominantly social, i.e. promoting interactions, creating a shared reality, or building social relationships. Quality is constructed in social interactions and used as a token therein. In the present paper we outline the social functions of quality, and discuss the implications of this perspective for designing more useful recommendation systems.