This study aims to describe students’ abilities in compiling thesis proposals and identify the easiest and most difficult sections along with the contributing factors. The study used a mixed methods approach with an embedded design, where document analysis of 26 student thesis proposals served as the primary method and in-depth interviews with 8 informants as the secondary method. The results showed that the average score for student proposals was 72.3, ranging from 57 to 86. The easiest parts of the proposal to master were the research background (average score 4.2), practical benefits (4.0), and operational definitions (3.9). Conversely, the most difficult parts were data validity (2.1), research instruments (2.2), consistency between proposal sections (2.4), limitation of focus and data (2.5), and research methods (2.8). Interviews revealed that the main cause of difficulties was not simply a lack of conceptual understanding (50%), but rather difficulty applying already understood concepts to their own proposals (transfer deficit) (62.5%), a lack of proposal writing practice (50%), a lack of sample instruments, and psychological factors such as laziness and social pressure (FOMO). This study recommends a shift in learning from a theoretical approach to guided practice, the provision of a comprehensive proposal example bank, and increased contextualized individual guidance.