Burndown charts are visual tools that help the team to track progress and see how they are performing compared to the planning. The chart also helps the team to track the amount of work and time remaining. You get your data for the burndown chart from the product backlog, the sprint planning and the amount of work done during the sprint. I will get into how to estimate the amount of work in later blogs. For now the focus is on how the burndown chart works.
The burndown chart shows the amount of work on the y-axis and the time remaining on the x-axis. It shows an ideal line and the line for actual delivery. The focus of the chart is to keep the remaining work on track. When the work is on track the orange line will be below or on the blue line. When the work is behind schedule the orange line will be above the blue line.
The pro's and cons of the burndown chart
When the work and scope of the project or sprint is highly predictable the burndown chart can be a powerful tool. But in projects with higher complexity it can become a drain on motivation.
I would advise using the burndown chart when you are reaching the finish line of a project or sprint and the amount of work is highly predictable. When there is a months of time left in the project as whole, the burndown chart can be counterproductive. People know there is a lot of work which they do not see yet, this can lead to apprehension after the first couple of sprints.
When scope creep is (practically) a certainty or work estimates feel like gambles instead of actual estimates based on the facts i do not use the burndown chart. The scope creep is difficult to represent in the burndown chart.