L'effetto del lean manufacturing sul benessere dei lavoratori: il ruolo delle pratiche lean soft The effect of lean manufacturing on employee weel-being: the role of soft lean practices

Today, lean is a widespread management approach in manufacturing companies, thanks to its proven positive impact on operational performance (i.e., efficiency, quality, flexibility and responsiveness). One aspect that remains barely comprehended by companies implementing lean, is the impact of lean practices on employee well-being. In particular, the present doctoral thesis is based on an analysis of scientific literature concerning lean and employee well-being. This analysis has allowed to detect that a clear-cut position is not yet available in the literature, and to highlight which are the main gaps. As regards the manufacturing context, Just-in-Time (JIT) practices have been mainly associated with worse working conditions, and soft lean practices (i.e., those lean practices related to employee involvement) have seemed to play a positive role for employee well-being. However, the discussion is far from being close and these lean aspects are rarely quantitatively assessed. Furthermore, few previous studies have quantitatively investigated the interaction between different lean-related aspects on employee well-being, with even inconclusive results. Starting from specific identified gaps, the present work develops several hypotheses based on lean literature and a consolidated psychological model, in order to further comprehend the impact of specific lean-related job aspects and their interaction, on two well-being measures, work engagement and exhaustion. The developed hypotheses have been tested through a quantitative study based on a questionnaire administered to 147 workers employed in an Italian plant of a multinational home appliances corporation. The results support the positive impact of soft lean practices on employee well-being, the negative impact of JIT-related work characteristics on employee well-being, the higher salience of soft lean practices on work engagement for those workers who perceive higher levels of JIT-related work characteristics, and the capacity of soft lean practices to alleviate the impact of JIT-related work characteristics on employee exhaustion. From the theoretical and practical point of view, the most important contribution of this research is represented by the quantitative confirmation of the ability of soft lean practices to mitigate the negative impact of JIT on employee well-being. The study also shows that workers exposed to more wearing conditions in terms of JIT, have a well-being level comparable with that of those colleagues exposed to less demanding conditions, thanks to their involvement in soft lean practices.