Goodhart's law

“When a measure becomes a target, it ceases to be a good measure”

An example A developer produces lines of code, that in itself can be measured. Without context, this is just a number. It say’s nothing of quality of the code produced, of value produced for a customer, of lowering of the cost of change¹ for future developers working on the produced lines of code. When a manager sets just lines of code as a target, what will be observed is an increase of lines of code produced.

The pitfall here is that without measuring quality² or other metrics for example, you might not achieve the goal you actually want. Since these other key metrics will suffer from the first measure becoming a target.

Source(s)

• https://www.wallstreetmojo.com/goodharts-law/
• https://youtu.be/kDBeFOscZpc
• https://modelthinkers.com/mental-model/goodharts-law
  • I want to dive into this one a bit more.

Footnotes

1. I should write something down on the cost of change and how it relates to the cost of software development (Tidy First,Kent Beck) ↩

2. I should write something about the DORA Metrics. ↩