CONCEPT
Conceptual Model
The user's mental representation of how a system works — accurate enough to predict, diagnose, and recover from the system's behavior — and the specific cognitive architecture that AI's probabilistic, context-dependent outputs systematically prevent from forming.
Norman placed the conceptual model at the center of his design philosophy. Unlike the engineering model (how the system actually works) or the design model (what the designer intended to communicate), the conceptual model is the user's internalized story of how the system behaves. When this model is accurate, the user can predict what the system will do, diagnose what has gone wrong, and recover from errors. When it is inaccurate, she is lost — acting on expectations the system does not meet, misinterpreting feedback, unable to learn from experience. The designer's task, in Norman's framework, was to shape the system's visible behavior into a coherent, comprehensible story that supported accurate model-building. AI systems, as Chapter 3 of the Norman volume argues, systematically resist this process.
In The You On AI Field Guide
The traditional conceptual model-building process worked because systems were deterministic and observable. The user pressed a button, observed the response, updated her mental model, and repeated.