PurposeVoice role identification and the psychosocial voice barriers represented by implicit voice theories (IVTs) affect lean team members' prosocial voice behavior and thereby lean team performance. This paper investigates how role definition and IVTs influence individual lean team-members' prosocial voice behavior during lean implementation.Design/methodology/approachThis research was conducted in four case readymade garment (RMG) factories in Bangladesh following a mixed-method research approach dominated by a qualitative research methodology. Under the mixed-method design, this research followed multiple research strategies, including intervention-based action research and case studies.FindingsThe findings suggest that voice role perception affects the voice behavior of the individual lean team members. The findings also demonstrate that voice role definition significantly influences individually held implicit voice beliefs in lean teams.Research limitations/implicationsThis research was conducted in four sewing lines in four RMG factories in Bangladesh. There is a need for a cross-sector and cross-country large-scale study that follows the quantitative research methods in different contexts.Practical implicationsThis research contributes to the operations management literature, especially in lean manufacturing, by presenting the difficulties of mobilizing employee voice in lean problem-solving teams. This work provides new knowledge to managers to address challenges and opportunities to ensure decent work and to improve productivity.Originality/valueThis research raises a key issue of employee voice and its influence on lean performance which addresses two critical areas of employee voice behavior in lean teams: team-members' voice role perception and implicit voice beliefs that influence their voice behavior in the workplace, thereby influencing team performance.