This study examines the effectiveness of Student Evaluations of Teaching (SET) at the University of Peloponnese (UoP), which has systematically collected anonymous evaluations since 2015. The analysis focused on participation rates, average scores, and the correlation between student evaluations and their academic performance. Participation rates were notably low, averaging 14.63%, with postgraduate students showing higher rates (27.33%) than undergraduates (10.77%). The average SET scores were moderately high, with postgraduates rating their courses slightly better (M=4.137) than undergraduates (M=3.899). A weak positive correlation was found between course grades and evaluations among undergraduates, whereas no significant correlation was observed for postgraduates. These findings highlight challenges in using SETs as reliable measures of teaching effectiveness and suggest the need for improved participation and more comprehensive evaluation methods. The results provide insights into enhancing assessment practices and contribute to the broader discourse on the validity of student evaluations in higher education.