Why do large-scale field experiments in education often have muted effects? Drawing on system dynamics and self-regulated learning theory, we sought answer this question by simulating the behavior of self-regulated (discrepancy-reducing) learners over time affected by different types of educational interventions. We analyze three types of interventions: changing students’ learning rates (learning strategies), intercepts (prior knowledge or teaching effectiveness), and norms of study (achievement goals). We uncover situations where educational interventions can affect achievement in the short run, but typical cross-sectional analyses do not find a measurable effect in the long run. Results indicate that highly motivated, self-regulated learners may resist external interventions, particularly those targeting learning strategies or prior knowledge. In contrast, interventions show the greatest effect on achievement when students are under time constraints and struggling to achieve their desired performance. Ultimately, self-regulated learners may be the hardest to help, a phenomenon we call the "self-regulated learning paradox."