What is an ideal sprint length?


What is an ideal sprint length?

July 20, 2015
What is an ideal sprint length? Image

Agile teams often face a challenge in determining how long their iterations, or sprints, should be. If sprints are too short, teams can get bogged down with prep work and overhead. In contrast, maturing teams may struggle to deliver working software in the demanding timeframe. However, longer sprints may also lead to wasted time for questionable added value.

To provide clarity to this challenge, NK Shrivastava of RefineM started a discussion on LinkedIn’s Agile and Lean Software Development group to collect opinions on the ideal length of sprints. His question was whether 2-week or 4-week sprints are better. We have seen that many teams coming to agile from waterfall will struggle initially to produce working software in a 2-week sprint.

Our interest was in finding out whether more agilists preferred 2-week sprints or 4-week sprints and whether the experience of agile teams is a factor. We expected that more respondents would prefer 2-week sprints to deliver working software faster, and collect more customer feedback. In this post, we discuss our findings and additional factors in determining your team’s ideal sprint length.

Two-week sprints

Two weeks was the most common sprint time reported among participants in our discussion. Multiple reasons were cited, with the main reason being more communication with customers. Two-week sprints mean that there are more reviews and retrospectives, presenting valuable opportunities for customer feedback and learning to take place.

The only downside mentioned with two-week sprints is that they are often difficult for teams that are new to agile. Teams’ early struggles may impact their ability to meet sprint goals for a two-week sprint.

Four-week sprints

In contrast with two-week sprints, few reasons were given as to why a team would want to adopt a four-week sprint. Some participants talked about the need to get new teams started with a longer sprint so they have a better chance to learn about agile ceremonies and practices. We have also seen teams that want longer sprints to grow accustomed to agile. Once they have grown accustomed to agile, however, they might be more comfortable reducing the sprint length to 3 weeks and then 2 weeks.

The downside of the four-week sprint is that it introduces what many participants referred to as a “mini-waterfall” effect. Because the sprint is so long, a lot of work goes untouched until late in the sprint, and then the team has to rush to complete everything on time. Four weeks is perceived to be too long for a customer to wait to give their feedback. If the team misses something critical or their approach is not viable, they lose more time figuring this out.

Factors Influencing Sprint Length

When NK asked whether 2-week or 4-week sprints are better, we expected a more even debate between 2-week and 4-week sprints. Surprisingly, the two most popular answers to the question were “2 weeks” and “It depends.” What it depends on are several factors that are worth keeping in mind when considering sprint length:

    1. Team experience with agile methodology.

This came up as one of the main concerns between 2-week and 4-week sprints. Less experienced teams often benefited from longer sprints until they developed the knowledge of agile and the capability to deliver working software in shorter sprints. In some cases, though, longer sprints were reported as masking problems, since it gave teams more time to deliver working software.

    1. Team size.

Some participants reported that smaller sprints were harder for smaller teams because they could not distribute the work adequately. With fewer people, each person has more to do, which means that tasks will take longer to complete and get to the testing phase. One way to account for smaller team size is to assign less work in each sprint, so each team member has a sustainable amount of work.

    1. Team location.

Teams working from different locations may want longer sprints to account for time spent coordinating meetings and communication. Ceremonies such as planning meetings and retrospectives may need more time due to distance between team members. Videoconferences may lag, for example, and the meetings may not be as effective if team members are not all in the same room. If teams need extra time for meetings and ceremonies, they may need to increase their overall sprint length to compensate.

In summary, from the majority of answers, two-week sprints seem to be the standard to follow. We expected this response, but many of the answers provided reasoning we had not thought about. Some participants echoed the concern we have heard about teams wanting more time if they are new to agile. Others, however, recommended that teams dive into 2-week sprints and do their best to fit that frame.

Based on the feedback, we recommend 2-week sprints as the standard. Conversations about ideal sprint length for your teams will be effective if they begin with two weeks and expand or shrink depending on team factors, including experience with agile, size, and location. Because team empowerment is important in agile, if the team is more comfortable with a longer sprint, encourage them to move forward and adjust as they learn more.

What are your thoughts on ideal sprint length? Please let us know in the comments. If your teams are struggling, you can see us about Agile Transformation services; we’re happy to help. You can also learn more about agile tools and ceremonies in our Knowledge Base.

Image taken from See-ming Lee, Flickr.

Posted in Blog and tagged , , .