A Rolling Stones shirt is a small piece of a much larger business. Inside Bravado, the Universal Music Group company that turns fandom into clothing, shops and second lives for unsold stock.

Before dashboards, agents and audit trails, Ralph Cavallaro learned systems thinking by producing a teenage punk band, washing cars to fund its record and calling college stations until they listened. Three decades later, the medium has changed; his habit of making unruly machinery usable has not.