A hesitant fuzzy linguistic QFD approach for formulating sustainable supplier development programs

Buying companies increasingly need to establish supplier development programs to improve the economic, environmental, and social performance of their suppliers. However, decision models that support the analysis and choice of sustainable supplier development programs (SSDPs) are relatively scarce in the literature. Given this context, this study proposes a model to support the formulation of SSDPs based on the HFLTS-QFD method, which combines Hesitant Fuzzy Linguistic Term Sets with the Quality Function Deployment technique. This model was applied to a European automotive company based on the judgments of an expert who evaluated six SSDPs regarding a set of buying company requirements. In this application, cost and quality were considered to be the most important requirements, whereas the programs related to the adjustment of production capacity, cost reduction, and the creation of a Kaizen system were classified as priorities for implementation. The results of the sensitivity analysis tests considering pessimistic and optimistic scenarios reinforced the robustness of the model. When compared with previous approaches, the proposed model presents several advantages, such as: it allows decision makers to use more than one linguistic term and linguistic expressions to evaluate buying company requirements and SSDPs; it considers the difficulty of implementation as a decision factor in selecting the most suitable SSDPs; and it provides an implementation ranking for the selected SSDPs based on the estimated implementation time and its potential to generate benefits for the buying company.