Despite the movement toward post-new public management in western countries, the new public (NPM) management model is still a popular managerialism adopted in many countries where the history of neoliberal governance is relatively short. While the principal-agent theory has been primarily used for analyzing education policy within the NPM context, previous studies have called for a better understanding of the principal-agent relationship when multiple agents behave strategically and consider other agents' behaviors. With an emphasis on the principal's role in designing a mechanism to generate desired outcomes using gamification, this article explores concepts for further research on policy evaluation in higher education. By contextualizing a theory-based evaluation of South Korean college admissions reform, I present a conceptual framework that better represents the dynamic relationship between a single principal and multiple agents and draws implications from the government's policy modification in obtaining the intended outcomes. This conceptual framework opens up new directions for research on educational policy, which calls for an alternative account of the responsibility of a principal in avoiding policy failure.