VRP revisited: The impact of behavioural costs in balancing standardisation and variety

The objective of this paper is to bring a new element to the academic (and industrial) debate concerning the optimum level of variety in component design in mass production companies. Many authors have explored the trade-off between functional and variety costs, and this could be considered as a well-acknowledged management issue, at least from an engineering perspective. Nevertheless, while defining the theoretically optimal level of component variety, there are other elements, more related to operators' attitude or to operative conditions, which may intervene and prevent effective exploitation of the existing variety. These elements have been given scant attention in literature, while they may play a relevant role in real organisations. In this paper, we will present a case study and an analytic model for these "behavioural costs" in manufacturing environments, so as to show how the theoretically optimal amount of variety changes if one takes into account these aspects. Researchers (and practitioners) might leverage on this contribution in order to rejuvenate the Variety Reduction paradigm, and to increase their awareness in designing and managing mass production manufacturing processes.