Toward Explainable Engineering Decisions: Pursuing a Descriptive Decision Theory at the Intersection of Analysis, Judgment, and Conviction

ABSTRACT Engineers design the technical systems that define and sustain our society. The decision‐making scenarios they face require both quantitative analyses and the consideration of qualitative factors, which are shaped by deeply held beliefs, values, and societal contexts. However, existing engineering decision‐making models, primarily derived from normative theories, fail to explain how engineers synthesize these diverse elements and arrive at a course of action, especially in situations with unresolvable uncertainties and conflicting information. To better understand and explain these engineering decision‐making processes, there is a need for descriptive decision‐making frameworks that can characterize the structured approaches engineers use. In this paper, we demonstrate how Conviction Narrative Theory (CNT), a framework developed from studies of business and finance decision‐making, can help explain how engineers frame decisions, integrate quantitative and qualitative information into cohesive narratives, assess outcomes, and commit to action amid uncertainty. Through three examples and results from an experiment, we show that engineers, even when full modelling and calculations are not feasible, use a structured narrative‐driven process to build conviction and justify their decisions. We also call for further development of descriptive frameworks like CNT to support the creation of robust, adaptable, and transparent decision support systems. Ultimately, explainable engineering decisions will enhance transparency, accountability, and collaboration among engineers, stakeholders, and the public.