Iteration Length |
This guideline describes how to measure and use the appropriate length for project iterations.
Main Description
### Overview The objective of this metric is to measure the length of iterations in a project. The software development lifecycle is divided into various iterations in order to be completed. Each iteration has a fixed duration, or a time-box. In most projects, the iterations length varies from four weeks to six weeks based on the size and complexity of project and work assigned to the iteration. If the planned iteration length is longer than six weeks, this would need a justification. The recommended iteration length is four weeks. This iteration length is typically long enough to allow work increments to be started and finished within an iteration, and at the same time is short enough to allow for setting up expectations from stakeholders that new functionality is added and available in a sustained, incremental manner. ### Measurement Method Total number of weeks planned for each iteration. ### Measurement Analysis The measurement analysis helps us understand if the length of project iterations is stabilizing successfully. Having stable, same length iterations makes it easier for teams to use other project and iteration metrics more efficiently and effectively, such as iteration burndown metric, iteration velocity metric, and so on. Generally, historical data is used for planning the iterations length in the beginning of the project. However, iterations length can be further adjusted based on current iteration situation and needs. The following figure shows a sample graph with plotted iterations length. In this graph, the length of the first two iterations is three weeks, because of factors like quick turn around capturing the requirements and creating initial design and implementation. Later in the project, when there are activities related to development, testing, review (with potential rework) and release, one more week is added to the typical iteration length, making iterations to be four weeks long.
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