This article shows how failed constitutional proposals may contribute to future constitution-making processes by exploring the relationship between the recently failed Chilean constitution-making process (2019–22) and the previous unsuccessful one led by former President Michelle Bachelet (2015–17). Comparative constitutional scholars are yet to fully understand how constitutional failures of this kind can take place, and Bachelet’s process has not received the attention it should. This article fills that gap by showing how both processes were driven by shared principles initially set by Bachelet. It also shows how those principles may serve as a blueprint for future constitutional changes in Chile. Bachelet had campaigned on the basis that any constitutional replacement attempt should be participatory, institutional and democratic – all ideas that have remained popular in Chile’s political landscape. Those ideas have served the purpose of both reducing transaction costs among constitutional negotiators and securing large compromises in polarized political scenarios.