You treasure what you measure: how KPIs make software dystopias

"Key Performance Indicators" -- KPIs -- are the metrics used by software shops to figure out whether their products are improving; notoriously, much of the software industry has converged on "engagement" (that is, minutes spent with an app) as a KPI, and everyone from designers to programmers to managers to execs earn their bonuses and promotions by making that number go up.

Absent any of this, "engagement" actually is a pretty good proxy for product quality: if your users voluntarily increase the amount of time they spend with your product, it's likely that they're enjoying themselves. But as Goodhart's Law has it, "when a measure becomes a target, it ceases to be a good measure."

For example, Google revolutionized the search industry by counting links to pages as a measure of the pages' relevance -- competitors like Altavista had been using textual analysis to decide which pages were most relevant to a given query, but Google's founders had the insight that when a lot of people across the web independently linked to a page, it was a good bet that something important was happening on that page.

The problem is that it's not hard to generate a bunch of links that look like independent links. So once Google's measure of page quality (inbound links) became a target for publishers, link farms were born, and the measure ceased to be a good measure.

The inspiration for Google's link-counting is an academic practice called "citation analysis," in which the quality of an academic study is judged based on the number of times it is cited. Read the rest