Process-control systems in Tanzania are critical for maintaining production efficiency across various industries. A mixed-methods approach was employed, combining quantitative data analysis with qualitative feedback from Tanzanian industrial practitioners. The application of a Bayesian hierarchical model revealed that system reliability could be improved by at least 15% through targeted interventions in critical components. Bayesian hierarchical models offer a robust method for enhancing the reliability and efficiency of process-control systems, providing tangible benefits to Tanzanian industries. Further research should explore the scalability of these findings across different industry sectors and geographic regions. The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.