Musk had deployed what he called the “idiot index.” That was the ratio of the total cost of a component to the cost of its raw materials. Something with a high idiot index—say, a component that cost $1,000 when the aluminum that composed it cost only $100—was likely to have a design that was too complex or a manufacturing process that was too inefficient. As Musk put it, “If the ratio is high, you’re an idiot.”
