This study explores the structural factors that determine why countries often get stuck in the middle-income trap. Analyzing a panel of 12 economies from 1990 to 2022, the research uses a dynamic System GMM model to address issues of income persistence and endogeneity. The findings confirm that gross capital formation is a robust driver of growth, while an aging population presents a significant obstacle. However, the results also challenge conventional wisdom. Instead of conditional convergence, the model reveals strong income persistence. Counterintuitively, both higher secondary school enrollment and greater export complexity were associated with slower growth in this context, whereas government expenditure was linked to growth. Notably, factors like institutional quality and R&D spending were not statistically significant. These complex findings suggest that escaping the middle-income trap demands a nuanced policy approach—one that looks beyond mere quantity of education and exports to prioritize quality, absorptive capacity, and the productivity of public spending.