A vast amount of research is devoted to identifying factors that predict early school leaving. However, there is no simple explanation because the results show that young people leave education prematurely for various reasons, such as their level of school involvement, their background characteristics and different school systems. This article investigates the importance of school motivation, self‐efficacy and the characteristics of students and their families for completing school and examines students in the vocational and academic tracks separately. With a focus on school completion, this study is guided by the following research question: Do students who obtain an upper secondary diploma have greater motivation and stronger beliefs about their abilities than those who choose to leave early? When adjusting for background characteristics, the results indicated no, or a relatively low, relationship between school motivation/self‐efficacy and completion. The most predictable variable is prior school performances, particularly for students in the vocational track.