There is a continuing interest in exploring the impact of operational excellence (OE) on operational performance. Several OE practices such as Lean, Agile, and Six Sigma are well recognised. However, not all OE deployments in firms have been successful, and a failure of such efforts has often been expensive. Past research reveals several critical failure factors (CFFs) that lead to OE deployment failures in firms. This research paper presents these CFFs as an integrated model, based on two dominant schools of OE that promote technical and behavioral factors independently. Further, the authors validate their direct and mediating relationships through an empirical examination of 663 responses collected from 153 manufacturing units across the USA, UK, China, and India. This article contributes to the OE body of knowledge by examining the significant direct and mediating effects of behavioural and technical CFFs on the OE failures. The research findings reveal that the technical CFFs mediate the impact of behavioural CFFs on OE failures. Consequently, several managerial and theoretical implications are presented.