Every student who drops out of a computer science program represents a missed opportunity, both for the individual and for the future of an industry that will need an increasingly skilled workforce. Nevertheless, the first-year dropout rate in Computer Science 1 courses generally ranges from 30% to 40% worldwide. Dropping CS1 hinders students' academic progression, often forcing them to retake the course. This also consumes significant university resources due to repeated assignment grading and raises the question of why so many students drop out of CS1. Understanding these factors can help educators identify opportunities to support better and maintain student engagement.

In this study, we employ a carefully designed questionnaire to investigate the reasons why students drop out of our CS1 course at a European university, which is attended by over 500 students each year. We collected 168 responses from students at various points throughout the semester to gain a deeper understanding of their expectations, challenges, and reasons for continuing or dropping out of the course. To capture their perspectives as close as possible to the point of dropout, we directly contacted them the day after early signs of leaving appeared, such as missing an assignment. Our questionnaire encompasses a wide range of potential influencing factors, including prior education, technical abilities, assignment difficulty, available support, and personal aspects such as time management, emotional stress, and motivation. This yields a dataset with quantitative measures and qualitative personal responses, capturing precisely the point at which disengagement occurs.

Our findings highlight that students with strong intrinsic motivation and a clear sense of purpose are significantly more likely to continue, regardless of their background or technical difficulty. External support structures—such as mentoring or structured feedback—proved helpful only when they reinforced that internal drive. By contrast, even well-prepared students tended to drop out when they lost sight of their reasons for pursuing their studies. Our work offers quantitative and qualitative insights into students' dropout behavior in a CS1 course. To reduce early dropout, universities must support students when initial signs of disengagement appear and focus on helping them build and maintain motivation from the beginning.

Keywords: CS1, Dropout, Computer Science Education.