A 'Law' That Was Actually a Self-Fulfilling Industry Roadmap

Moore's original observation was descriptive — transistor density on chips had roughly doubled every couple of years, based on a handful of data points. It wasn't derived from a fundamental physical constant the way, say, the speed of light is. And yet it held for decades, far longer and more precisely than a rough early observation usually would.

The reason is that the semiconductor industry treated it less as a prediction and more as a coordination target — equipment makers, chip designers, and fabrication plants all planned multi-year roadmaps assuming the trend would continue, which meant enormous coordinated investment was aimed specifically at making it continue. The "law" partly held because everyone acted as if it would.

This is a useful case study in a broader pattern: some trends persist not because of an unchangeable underlying force, but because an entire industry organizes its incentives around making the trend true. Understanding which category a trend falls into matters enormously for predicting when it will finally break.