What get’s measured, get’s managed.
I’m not a fan of clichéd sayings, but sometimes they are often repeated for a good reason. They point to a truth that’s easily wrapped in words. Metrics are important because you can’t gauge your progress without it. You can’t know what and how well you’ve done something unless you have something to measure against it. When picking a metric, you have to keep in mind what you’re trying to measure, where you’re trying to progress to, and most importantly why. Always make sure the reason why you’re trying to measure and develop something will actually get your from point A to point Z.