Velocity is one of the key metrics used by Agile teams to measure the rate at which a team delivers value to the customer. In his book “Escape Velocity – Better Metrics for Agile Teams”, Doc Norton explains why velocity is not the ideal metric for Scrum teams. In this quote, he discusses the complexity of the system that underlies the velocity metric.
This is ultimately quite significant. Velocity, while a simple concept, is actually a measure of output for a complex system. Think about the number of factors that go into a velocity measurement. There is the organizational mission, the broader business objectives, and the objective of the product itself. There are product owners, designers, architects, developers, testers, subject matter experts, security specialists, database specialists, governance, and production specialists involved. There are stand-ups, planning meetings, and retrospectives. There are epics, stories, and tasks all tracked on a board or in a system with multiple lanes representing different key states in the delivery of each single piece of work. After all these individuals interact with one another, responding to change, and collaborating with the customer in pursuit of working software, we take a single measurement. That single measurement represents the interactions of the individuals and all of their adaptions to change in the delivery of working software.
Velocity is a simple measure of a very complex system. To measure creative work by throughput alone is to not measure it at all; quality and impact are essential. While a simple measure of a complex system may sound ideal, in this case, it is generally insufficient. Velocity doesn’t tell us enough to be particularly useful. From velocity alone one cannot ferret out root causes. On cannot determine conclusively that the team is doing better (or worse) from a rising (or falling) velocity. Velocity is but one dimension to consider. To measure creative work by throughput alone is to not measure it at all; quality and impact are essential.
Source: Escape Velocity – Better Metrics for Agile Teams, Doc Norton, https://leanpub.com/escapevelocity