In the summer of 2014, Aruna Ranganathan was doing postdoctoral research at a garment factory in Bangalore, India, when she noticed that some worker stations—but not all—were equipped with radio-frequency identification (RFID) technology, a tool used to quantify workers’ output.

Ranganathan, now an associate professor of organizational behavior at Stanford Graduate School of Business, wondered how the technology impacted workers’ productivity, a topic that’s received little attention.

So she spent the next several months embedded in the plant, then analyzed multiple years of the factory’s data to find out. Ultimately, she discovered that when companies quantify simple tasks, productivity goes up. Quantifying complex work, however, has the opposite effect: It drives productivity down.

What’s behind this phenomenon? When workers completing simple tasks have their work quantified, they’re more likely to turn the experience into a personal game, a concept known as “auto-gamification.” They compete against themselves to increase efficiency, even when there’s no reward for doing so and no punishment if they don’t.

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