Academic struggle is a concern for students, medical schools, and the society. As academic struggle is not idiopathic and instantaneous, qualitative research could provide an in-depth understanding on why it occurs. This qualitative research aimed to explore reasons of failure among Malaysian Year 1 struggling medical students through the lens of Theories of Action. This study adopted a single, embedded case design. Six medical students repeating their Year 1 studies performed a written reflection describing their experiences and behaviours during Year 1. Then, semistructured interviews were conducted with each student, and data were analysed by two researchers. Independent analysis was compared, and discrepancies were resolved through discussions between the researchers. Each student narrative demonstrated difference in behaviours and experiences. Students showed limited learning engagement or demonstrated ineffective learning methods. Narratives indicated various reasons such as being overconfident or unmotivated to study for these behaviours. However, interpreting based on Theories of Action, the students’ failures could be explained by three types of invalid governing variables found in the data. Students may have performed their actions based on inadequate knowledge, possessing misbeliefs, or demonstrating no rationales at all. Invalid governing variables may have led to ineffective actions, and subsequently, resulting in unintended consequences. Hence, all students failed the mid-year and/or end-year assessments. Struggling students lacked the valid governing variables in rationalising their actions. Based on the Theories of Action, to deeply assess and alter their governing variables, struggling students are recommended to perform double loop learning.