There are many measurements that we can use to give us an idea of how our team is performing. Before we start tracking metrics, it's important to understand that what we measure is what we get. 

For instance, velocity is a standard measurement used by Scrum teams. It tells us how many User Story Points we're completing on average in each Sprint. As we'll explain further in the Negative versus positive section, it's a measurement that is used mainly by the team to help them understand how they are performing. If used out of this context, it can cause adverse effects which can make the metrics meaningless.

A lot of measurements work in the same way; that is, they're meaningful to the team but less useful to those outside it. They don't always mean much in isolation either; we often need to compare and contrast them with other metrics. For example, the percentage of code covered by automated tests is useful if the quality of those tests is also measured.