The Metric That Ruins Everything
How Goodhart's Law Quietly Ruins Every Product It Touches
When a proxy measure becomes the goal, the actual goal collapses, turning time-on-page into doomscrolling and engagement into outrage.
Software teams track everything now. Time spent on page. Click-through rates. Conversion funnels. Engagement scores. Heat maps showing where eyes linger. Every interaction becomes data, every behaviour a metric to optimize.
Then someone decides which metric matters most. That’s when things break.
Consider a news app optimizing for “time spent reading.” Sounds reasonable. More time reading means more engaged readers, right? So designers add infinite scrolling. Autoplay videos. Related article suggestions that never end. Clickbait headlines engineered to keep you scrolling.
The metric improves. Time spent skyrockets. But nobody’s actually reading anymore. They’re scrolling, skimming, chasing the next headline. The proxy measure (time spent) became disconnected from the actual goal (informed readers).
This pattern repeats across products. A shopping app focuses on conversion rates, so it adds aggressive pop-ups and manipulative countdown timers. Conversions increase. Customer satisfaction craters. The metric wins. The experience loses.
Social platforms optimize for engagement, which sounds innocuous until you realize engagement means any interaction. Rage-clicking counts. Hate-sharing counts. Doomscrolling at 2 AM counts. The algorithm doesn’t distinguish between “engaged because delighted” and “engaged because enraged.” It just wants you clicking.
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FAQ
- What is Goodhart's Law in product design?
- When a proxy measure becomes the goal, it stops being a good measure. A news app optimizing for time spent reading adds infinite scroll and clickbait. Time skyrockets but nobody is actually reading. The metric wins, the experience loses.
- Why do social platforms reward outrage?
- Platforms optimize for engagement, which counts any interaction equally. Rage-clicking, hate-sharing, and doomscrolling all register the same as genuine delight. The algorithm doesn't distinguish between engaged-because-happy and engaged-because-enraged.
- What are some related topics to explore?
- Goodhart's Lawvanity metricsdark patternsengagement optimizationproduct design ethicsdoomscrolling
Defined Terms
- Goodhart's Law
- The principle that once a measure becomes a target, it ceases to be a good measure.
- Dark patterns
- Interface choices designed to mislead users into actions that benefit the platform at their own expense.
Foundations
- Over-optimization of academic publishing metrics: observing Goodhart's Law in action
- GigaScience, Oxford Academic, 2019
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