This article is a product of a study that deployed a qualitative research approach to examine what motivates students in Tanzania to undertake postgraduate studies, and the causes of late completion of such studies. A total of 47 participants were involved in this study through focused group discussions and semi-structured interviews. The results revealed five distinct reasons why postgraduate students enter a doctoral or master’s degree course: employment prospects, better salary, career progression or change, personal development, and prestige or self-actualization. Moreover, it was found that the determinants of late completion were both institutional and personal. Institutional factors included a non-supportive learning and research environment, cumbersome thesis and examination process, heavy supervisors’ workload, supervisors’ lack of motivation, and low entry qualifications by candidates. On the other hand, personal factors were poor educational background, social and financial problems, lack of good communication skills, research incompetence, low commitment, and partial study leave. The study concludes that efforts to improve the quality of postgraduate training should address the potential systemic, institutional and individual barriers. In the light of this, it is recommended that the institutional conditions and policies should be re-examined to ensure that supervisors and those they supervise are effectively facilitated in fulfilling their roles and responsibilities, so that postgraduate research produces good and timely quality results.