Ah yes, the velocity chart.
The agile metric that is often used to compare different teams, even though it probably should not be used this way. In general, the velocity chart is also known as just velocity. Usually you would encounter this when colleagues or stakeholders ask the classic question of: "what is your velocity?".
That question is often asked, since the velocity chart helps teams measure how much work is completed in a given period. When the period of time is fixed, and you measure completed work iteration after iteration, the velocity chart can provide insights into the team's productivity, consistency and predictability. Used incorrectly, the consequences can be significant and harmful.
Let’s dive into the velocity chart together and see how to use it correctly.
What is a velocity chart?
I will give you a one-sentence definition of velocity charts later, but first I would like to frame a scenario that helps you understand this metric even better. This also helps avoid confusion on this metric versus other metrics, and the scenario I will use is as always: packing boxes before relocating into a new home.
You have signed a deal with a moving company, whom will come by to transport boxes to your new home. They will come in a month from now, and you should have packed everything that needs to be moved before then. This gives you 4 weeks of time to pack your boxes. Following is your performance of packing boxes:
- Week 1: You pack 3 boxes.
- Week 2: You pack 10 boxes.
- Week 3: You pack 3 boxes.
- Week 4: You pack 4 boxes.
In total, you have packed 20 boxes and are now ready to move. Each week, the number of boxes packed represents your output, or the amount of work completed. If we track these numbers over time on a chart, we would see a bar or line for each week, showing your velocity for each period towards relocating to a new home, which is why it is called a velocity chart.
You can use this metric to derive a few insights. One is that your velocity is closer to 3-4 boxes a week, and you only managed to pack all 20 boxes because of the burst in productivity in Week 2. Therefore, understanding why your velocity was higher in Week 2 might help improve your velocity in other weeks. At the same time, it will be difficult to commit to a 4 week timeline again, if we remove Week 2 as an outlier. A realistic timeline would have been 5-6 weeks, when considering the velocity of packing 3-4 boxes a week. An optimistic timeline would have been 2 weeks, if you can replicate and implement the productivity seen in Week 2.
The more data you have of your past performance, the better you can use the velocity chart as a metric to plan ahead and identify patterns, which can pin point improvement areas in your team.
Based on above, let's try to create a simple one-sentence definition.
Simple definition of a velocity chart
A velocity chart is a graph that tracks completed work over time, displaying an upwards or downwards trend depending on a team's productivity.
