The Sustainability Paradox in Digital Behavior Change Interventions: Narrative Ownership as a Design Principle for Lasting Change.

Unlabelled: Digital behavior change interventions (DBCIs), including smartphone apps, wearable devices, and AI-driven adaptive systems, have become a dominant approach for promoting changes in health-related behavior. Although meta-analyses have consistently demonstrated short-term effectiveness, a recurring finding is that these effects are attenuated once user engagement declines or the intervention ends. We describe this phenomenon as the sustainability paradox: the same design features that maximize behavioral success during use, such as automated guidance, real-time feedback, and gamified rewards, may undermine the conditions necessary for the behavior to persist once the intervention is terminated. This viewpoint introduces narrative ownership as a conceptual framework for understanding and addressing this paradox. Narrative ownership refers to the extent to which individuals experience behavior change as an ongoing, interpretable, and self-authored process and comprises 3 components: process framing, narrative repair, and authorship. We argue that many contemporary DBCI architectures unintentionally displace these experiential processes by automating lapse correction, redirecting behaviors without interpretation, and externalizing the attribution of success. We map these tendencies onto 3 structural mechanisms-the erosion of process framing, the foreclosure of narrative repair, and the hollowing of authorship-and distinguish narrative ownership from adjacent constructs such as engagement, self-efficacy, and autonomy support. We also note that narrative ownership is double-edged: the same reflective processes can consolidate negative self-attributions, and its expression varies across cultural contexts, taking a familial or communal rather than strictly individual form in relational settings. Therefore, to translate this framework into practice, we outline 3 design principles for sustainable digital interventions: reflective pauses that support process framing, lapse reinterpretation features that enable narrative repair, and meaning-linking interfaces that strengthen authorship. For each principle, we derive testable propositions-for example, that reflective pauses will improve behavioral maintenance after the intervention ends and that meaning-linking interfaces will sustain behavior after app use is discontinued-along with candidate outcome measures and directions for empirical validation. Together, these principles reposition the user not merely as the recipient of behavioral guidance but also as the author of their own story of change in digital health interventions.