Non-Mediated Power and Supplier Performance in the South African Construction Industry: The Mediating Role of Relationship Strength

Abstract

This study explores the association between non-mediated power, relationship strength, and supplier performance metrics in the South African construction industry. The study used a quantitative methodology to examine 389 construction industry professionals from Gauteng and KwaZulu-Natal. Data were collected via a structured, self-administered survey and analysed using partial least squares structural equation modelling (PLS-SEM) and descriptive statistics through SPSS. The results revealed that referent and legitimate power positively influence relationship strength, which enhances supplier quality and delivery performance. However, expert power did not significantly affect relationship strength, and the latter did not considerably impact supplier cost, flexibility, or sustainability performance. The findings highlight the nuanced role of social power sources in shaping supplier outcomes. This study contributes to the literature on supply chain management by introducing a novel model linking power dynamics, relationship strength, and supplier performance. The results supported the social exchange theory and contingency theory. The study provided actionable insights for construction firms aiming to optimise supplier relationships and performance. The originality of this study lies in its examination of non-mediated power's function in improving supplier performance via relationship strength in South Africa's construction industry. It provides actionable insights for construction firms aiming to optimise supplier relationships and performance.