Introducing decision sovereignty: A missing transmission variable in models of implementation

Why do well-informed decisions so often fail to translate into sustained action? This research note introduces decision sovereignty as a missing transmission variable between decision quality and implementation in complex institutional and behavioural systems. While advances in data, analytics and artificial intelligence have dramatically reduced the cost of prediction, realised outcomes have not increased proportionately. The paper argues that this disconnect arises from an endogenous execution constraint: governance structures designed for lower decision intensity impose convex costs as decision volume, scope and contestation increase. Decision sovereignty specifies the institutional capacity to select a course of action and carry it through to completion despite internal fragmentation and external pressure. Introduced as a boundary-condition variable rather than a substitute theory, decision sovereignty clarifies when improvements in predictive capacity translate into outcomes and when they do not. The paper develops a reduced-form representation, proposes a conceptual Decision Sovereignty Index, and outlines falsifiable implications for future empirical research.