Agilists all over the world often ponder over this million-dollar question. Should sprint lengths be fixed or variable?
And if it does need to be of a fixed length or of a short duration, then what is the rationale for scrum teams implementing short sprints?
Is it to adhere to the core idea of Agile, which is to work fast and work smart or is it to ensure continuous improvement?
Let’s delve into what exactly works when it comes to sprint lengths and how Scrum Masters should choose the ideal sprint length for their teams.
What is sprint length in Scrum?
A sprint is a timeboxed period within which the team is expected to deliver a working product of good quality to the customer.
Although there is no fixed length for a sprint, the general rule of thumb is that it should be long enough to develop something while short enough to ensure that not too many uncertainties creep in.
The heart of Scrum is a Sprint, a time-box of one month or less during which a “Done,” useable, and potentially releasable Product Increment is created.
Who decides the sprint length?
The Scrum Guide does not impose a fixed time length on the sprint duration. It falls to the discretion of teams to decide what length suits them best and is most productive.
Sprints can be as short as 1 week or as long as 1 month.
What happens when the sprint is short?
Typically, short sprints are of 1-2 weeks duration.
- Problems are identified sooner.
- Teams must ensure that impediments are resolved faster.
- The final time-to-market is quicker.
What happens when the sprint is too long?
Typically, long sprints last for 3 weeks to a month.
- A longer duration may lead to end goals changing.
- Complexity and risks may arise thereby leading to more costs and unpredictability.
- Greater chances of sprint getting cancelled.
- More uncertainty as risks and team problems may get addressed slowly.
According to the 2015 Q1 Agile State of the Art Survey Results, 65% Agile teams have 2-week sprints, which leads us to conclude that Agile teams prefer to have short sprint lengths rather than long ones.
What is the rationale for scrum teams implementing short sprints?
Getting a product out in a one or two-week duration may seem impossible at first. Teams may be tempted to go in for the longer sprint as it would mean lesser stress and more time to get the product out.
But this short gratification can have serious consequences. A long sprint may lead to other problems such as a never-ending list of new features being added mid-sprint, a tendency to overlook risks and fewer opportunities for the team to show the stuff they are made of and become exceptional.
Shorter sprints, though stressful at first, eventually help teams work better and meet goals faster.
Top 5 Reasons Why Scrum Teams Implement Short Sprints
1. Short Sprints of a Prefixed Duration Bring Stability
Regular time-boxed delivery is the core Scrum discipline; therefore, we can’t take the liberty to have flexible sprint lengths. In case of flexible sprint lengths, team members are unsure of schedule.
The fixed duration sprint benefits the Scrum teams because each member settles down to the rhythm. Shorter sprints translate to shorter retrospectives and targets that the team can achieve faster.
2. Sprint Planning Becomes Easier
Sprint planning is the key to ensuring that your agile project goes as planned. This collaborative meeting requires inputs from all members of the agile team.
Shorter sprints make planning easier. Team members know how much work they are supposed to deliver in the forthcoming sprint.
With shorter due dates for each task to be completed, it is easier to track tasks that are ‘done’ and assign tasks that are ‘doable’. This does not unnecessarily stretch team members with unrealistic dates, helps maintain focus and reduces ‘Dark Scrum’.
3. Tracking Velocity Is Easier
Velocity is one of the most important metrics in Scrum and refers to the amount of work a team accomplishes at the end of the sprint.
A short sprint helps you to develop a better definition of done and stabilise velocity. With longer and flexible sprints, you can’t be sure of completing twice the amount of work if the one-week sprint period is extended up to two weeks.
The alternative practice may be to normalize the velocity on per-week basis, but it seems a needless and complex exercise if the Scrum sprints are kept at the same length.
4. No Mid-Sprint Requirements
Imagine this scenario; you decide on a sprint duration of 1 month. You are happy that you have a lot of time to get your product out. Mid-way through your sprint, your product owner comes up with a whole new set of requirements.
Or worse yet, there have been market changes and your customer has new expectations, thus changing the entire goal of your sprint.
Now, you either are at a risk of getting your sprint cancelled or have to rush to complete the product incorporating all the new changes, often a situation that results in quality being compromised.
In contrast, a short sprint ensures that there are more frequent sprint reviews. These frequent interactions give the product owner a better chance to understand the product and allowing the team to manage the scope of their sprints.
So, shorter sprints = fewer number of disruptions = more work accomplished.
5. Maintaining the Essence of Scrum
A short sprint helps you uphold all that Scrum stands for, including fast feedback, continuous team improvement, high motivation, fail fast and fail safe, more feedback cycles, and more frequent release of working software,
How to Fix the Ideal Sprint Length – 5 Tips
1. If you have continuously changing requirements
If you are working on a product that has constantly changing requirements, either due to changing customer expectations, market conditions, or changing technology, then having short sprints is the way to go.
2. If your team performs well under pressure
You have built your team and you know every team member’s work ethics. If your team is highly motivated and thrives under pressure, then short sprints are perfect for your team.
Shorter deadlines require teams than can stretch themselves thin and give the expected output.
Even if you have a team that likes to procrastinate, and leave things till the end, shorter sprints may force them to change their working style and work at a consistent pace to match sprint goals.
3. If your team is new
If your team is new, you do not yet know how they work and what they are capable of, then you would need to experiment with flexible sprint lengths.
This is a trial-and-error approach and as you and your team members get familiar with each other and the output required, you will be able to fix the sprint length. Do not be weary of experimentation as this will help you decide on the ideal sprint length.
4. If there are too many impediments
If there are too many obstacles that disrupt your sprints mid-way then it is better to have short sprints.
5. If you are using TDD
Good engineering practices such as Test Driven Development significantly reduce testing time that may need to be performed during software development, thereby resulting in shorter sprints. The products created have fewer defects.
So, if you are using TDD to develop your software, you can fix your sprint lengths to 1 week or less.
Good sprint planning is the most effective way to ensure that your team works well. Shorter sprints help you reach goals faster and release working software more frequently at a steady pace.
Your customers are happy because they are getting what they need really fast and your team members are happy since they are getting appreciated, are able to meet goals and are highly motivated.
The short and long of it though is that, once the sprint length is decided, the team should stick to it. Going with a flexible sprint length can open a whole new can of worms and can be detrimental to the project success and team morale.
At the end of the day, every team has to decide what works best for it, but going by statistics, short sprints are the way to Agile success!