Every metric that becomes a target looses its value as a metric. The specific phrase “when a measure becomes a target, it ceases to be a good measure” is known as Goodhart’s Law. It originates from British economist Charles Goodhart, and the exact modern phrasing was popularized by anthropologist Marilyn Strathern. Core Ideas of Goodhart’s Law A Practical Way to Think About It Treat metrics as signals, not goals. Use them to start conversations, not to close them. Combine quantitative KPIs with qualitative checks (code reviews, incident deep-dives, customer feedback) so no single number can be gamed without being noticed. Goodhart’s Law exmaples in Business Goodhart’s Law exmaples in Education…

Yes, this pattern has names and precedents. Martin Folwer official site. Sits boldly and pains some developers… at the intersection of a few well-known ideas. Helps as and works a “fill in the gaps” kind of approach. Names / related patterns But Hey ! It is “heresy” to put tests in production code? Feels counter‑intuitive only if you equate “tests” with “unit test files that should never ship”. Advocated by people is a yes or not purely based on their experience. If it works for You – go for it ! You can always remove it later. If it helps You in any way, the idea is just. There is…