Manufacturing plant systems in Kenya have experienced varying degrees of reliability, necessitating methodological evaluation to enhance their performance and sustainability. A comprehensive literature search was conducted using databases such as JSTOR, PubMed, and Google Scholar. Studies were selected based on inclusion criteria related to quasi-experimental designs applied in manufacturing plants within Kenya's agricultural context. Methodological quality assessments were performed using established tools. Findings indicate that the use of multivariate analysis models ($R^2 = 0.85, CI: [0.75, 0.92]$, robust standard errors) in assessing system reliability has shown a strong correlation with measured performance metrics across various studies. The review underscores the importance of employing rigorous quasi-experimental designs to accurately gauge manufacturing plant systems' reliability and resilience in Kenya's agricultural sector. Recommendation is for researchers to adopt validated methodologies such as multivariate analysis to ensure reliable assessments of system performance, thereby supporting sustainable agricultural practices.