In an era of test-based accountability, school inspections can offer a more nuanced understanding of why schools fail. Yet, we have limited knowledge of how inspectors arrive at their decisions on school quality. Analyzing inspectors' decision-making can reveal the underlying views regarding school accountability and open opportunities for school improvement. We use a comparative case study of contrasting inspection systems in the United States, the Netherlands, and Argentina. Based on in-depth interviews with inspectors, our findings reveal that inspectors' sensemaking and decisions are strongly influenced by local culture, professional traditions, and views on school accountability. These contrasting processes illustrate trade-offs between rigid and flexible approaches to school inspection that have consequences for school improvement.