The first measurement can quietly become the definition of success.

Whatever you measure first tends to become the definition of doing well, simply because it is the thing being tracked. The metric was originally a proxy for something you actually cared about, and over time the proxy quietly takes the place of the goal, and people start optimising the number rather than the thing.

Revisit what you are tracking and say out loud what it was supposed to stand for. Then ask whether the two have come apart. If you can push the number without improving the underlying thing, you have found the drift, and it is worth correcting before it becomes the culture.