The Relationship Between HR Devolution to Line Managers and HRM Effectiveness in Nigerian Fast-Growing Companies

This study examines the relationship between the devolution of HR responsibilities to line managers and HRM effectiveness outcomes in fast-growing Nigerian companies, particularly within the fintech, e-commerce, and retail sectors that have expanded rapidly in recent years. As Nigerian companies scale quickly, they frequently rely on line managers to execute HR practices, yet the readiness, motivation, and capability of these managers for HR-related tasks significantly determines HRM effectiveness in practice. The study employs a mixed-methods design, combining survey data from 195 line managers, HR business partners, and employees across 16 high-growth companies with qualitative interview data from 12 HR directors. The Perception-Practice Gap Framework and Role Theory provide the theoretical grounding. Quantitative findings reveal that the degree of HR devolution is positively associated with HRM effectiveness when line managers have received adequate HR training and feel ownership over people management outcomes. However, devolution without capability development generates a significant perception-practice gap: line managers report performing HR tasks that their direct reports assess as ineffective. The study also documents that performance management execution quality is the most variable HR practice across line manager cohorts. Qualitative data reveal that time pressure and competing operational demands are the primary barriers to effective HR delivery by line managers. Recommendations include structured HR capability programmes for line managers, HR business partner coaching support, and accountability frameworks for people management. Keywords: HR Devolution, Line Managers, HRM Effectiveness, Fintech, Fast-Growing Companies.