The high failure rate of projects has prompted researchers and academics to investigate the determinants of project success. Consequently, a substantial body of research has explored why project managers fail to deliver. However, no comprehensive quantitative analysis of the extensive literature on this topic has been conducted until now. We address this gap by conducting a bibliometric study on the relationship between project managers' demographic characteristics and project success. First, we analyzed 397 articles published in Scopus between 2000 and 2024 using co-citation analysis, which revealed five theoretical foundations: strategic framework, leadership qualities, risk management in projects, human skills, and critical success factors. Additionally, co-occurrence analysis identified six prominent research streams: technological resources and innovation, the construction industry, project success and governance, project design and control, project complexity, and new product design. Second, we manually reviewed 103 of the latest documents published during 2021-2024 to identify major methods, theories, and frameworks. These documents were then used for bibliographic coupling, which highlighted six key research areas: team characteristics, project evaluation and assessment, competencies, emotional intelligence and behaviors, project control systems, and leadership qualities. Based on the outcomes of the co-citations, co-occurrence, and bibliographic coupling analyses, we developed a conceptual framework that integrates past and present research streams and identifies several future research directions for scholars and academia.