Democratically elected incumbents have engaged in subverting democracy without losing popular support in several countries in recent years. It remains a puzzle that this phenomenon has occurred in relatively mature democracies. In this research note, I argue that citizens become less likely to sanction undemocratic behaviour as their country gains democratic experience because they lose incentives to form opinions on the basis of threats to democracy. Using macro-level panel data on democratic experience, undemocratic incumbent behaviour and incumbent approval across 43 democracies from 1962 to 2018, I find that undemocratic incumbent behaviour decreases incumbent approval when democratic experience is low. As democratic experience increases, however, this effect fades out. These findings question whether we can count on citizens to be the backbone of democratic stability in countries with democratic experience.