An investigation of design trade-offs in the automotive industry

This study aims to improve the understanding of the rationale behind decision trade-offs in design. A case study of a mass-market car manufacturer was conducted, through interviews, qualitative questionnaires and observation. The study revealed that decision making practices in trade-off situations follow a series of patterns, in the way that decision makers perceive the relative importance of the design targets and the criteria involved in the trade-off. These practices are not formalised and remain implicit in the larger mechanisms of car design and development and often contradict the technical guidelines for making trade-offs that exist in the company. These patterns have been formalised into a framework which explains the rationale of design trade-offs. The paper shows how this framework can be applied to the analysis of design trade-offs in a general design organisation and discusses its importance for practitioner designers and design researchers.