The Universal Periodic Review (UPR) of the Human Rights Council is still the most innovative monitoring mechanism in the UN system. Despite operating on a voluntary basis, it has successfully completed three review cycles with universal participation. The activism of recommending states in the UPR interactive dialogue is fundamental to keep the mechanism going and has captured much scholarly attention in the last decade. However, we know little about silence in the UPR. Why do states choose not to make recommendations to states under review? Rationalist and non-rationalist IR theories provide different reasons for states’ lack of cooperation with international institutions. This paper applies these theories to the UPR setting and tests hypotheses that explore instrumental and normative explanations. The paper differentiates between consistent and selective silence, and presents evidence from statistics, interviews, and network analysis to show that silence is mostly explained by incapacity and that, when instrumentalised, it has the purpose of punishing instead of protecting states under review. This last finding invites us to revise theorisations on states’ behaviour in the UPR which treat it as a shaming mechanism.