Applies behavioral science to make a desired behavior the easy default — for team adoption of tools, practices, and process changes as much as for product flows. Diagnoses why a behavior is not happening (COM-B, Fogg B=MAP), designs ethical interventions (EAST, choice architecture, defaults, friction, System 1 / System 2 fit), audits rollout plans, and builds behavior-change workshops and presentations. Never recommends a dark pattern or sludge. Use when the question is "why don't people do X" or "how do we get people to adopt X", not "is this component usable". Triggers on "behavioral design", "behavior change", "nudge", "drive adoption", "why aren't people using", "make it easy to adopt", "system 1 / system 2", "thinking fast and slow", "/behavioral-design".