To assess the time needed to complete a project, story points are one of the Scrum tools favored by development teams. Indeed, this method is an increasingly popular alternative to the traditional person-day estimate since it does not focus on a hypothetical duration but on the amount of effort to be provided.
If this is the first time you’ve heard of story points, you may feel confused because this technique is more intuitive than associating several hours with tasks. Please do not panic; today, we bring you to the discovery of story points: we will explain what is precise, return to their advantages, and calculate them at best.
What Is A Story Point?
Story points are a measurement unit used mainly in agile Scrum project management. They are used to estimate the overall workload of the teams to plan each sprint or iteration better. Concretely, a number, or value, is assigned to each user story (or user scenario ) to evaluate the total effort (energy, workload, etc.) allocated to its realization. Consequently, the story point estimation must consider all the parameters that impact this effort:
- the amount of work to be done;
- any risk or uncertainty that could compromise their achievement;
- the technical capabilities of the team.
Story Point VS Day/Man
But why not use the traditional count in days/man to determine the teams’ workload? Quite simply because the latter fluctuates according to the people; for example, a senior developer and a junior developer will only need a different amount of time to complete a similar task. Story points eliminate this problem because the estimate no longer depends on the person in charge of the user story.
- Ultimately, story points are beneficial for:
- reduce risks and grey areas in estimates;
- gain in precision, efficiency, and flexibility;
Adapt to people, and establish trust and benevolence within the project team. When to calculate story points? Story points are usually awarded when defining user scenarios, especially during backlog refinement. Upstream of each sprint, the product owner prioritizes future user stories to work on.
Then the project team estimates the effort necessary for their realization because it has a limited time (a sprint) to complete the selected scenarios. It is essential that the whole team acts together to determine the story points. Indeed, each member has expertise and experience regarding the specificities of this or that development to be produced.
How Do I Get Started With Story Points? The Five Steps To Follow
Step 1: Understand The Story Point Rules
The values and meanings of story points remain specific to each project and organization. However, some rules remain universal:
- Each story, whatever its nature, is assigned a certain number of points.
- The quantification of the effort to provide per story point must remain stable at each sprint and from one story to another.
- Two story points equal twice the effort compared to 1 story point. Three story points at three times the action compared to 1 story point…and so on.
The number of points your award does not matter. What matters is the ratio. Ultimately, story points are a tool to demonstrate the relative effort between each user story and each sprint.
Step 2: Set The Story Point Value
As we have seen, the value of story points remains relative. However, we will provide some basic estimates to provide a frame of reference. For example, be aware that many teams use the Fibonacci sequence (1, 2, 3, 5, 8, 13, 21, 34, 55, 89, etc.) for their estimates rather than a linear ascending sequence ( 1, 2, 3, 4, 5, 6, 7, etc.) or a series of random numbers.
What are the advantages of the Fibonacci sequence? Unlike the linear scale, the intervals between the numbers in this series are increasingly widespread. Consequence: the estimate is less precise as the value increases, which better reflects the uncertainty inherent in large-scale projects.
Step 3: Analyze User Stories
Once you have determined the values associated with your story points, and before making concrete estimates for your user scenarios, it is worth analyzing in more detail:
- the nature of the future tasks to be performed,
- their complexity,
- the risks and uncertainties the team may encounter along the way.
Some tips :
- Please measure the size of each selected user story as accurately as possible, calculating the number of tasks and subtasks needed to complete it.
- Assess the actual complexity of the tasks. For example, writing 100 standard two-sentence messages differs from creating ten full technical descriptions. Even if the latter requires fewer subtasks, it will mobilize more effort.
- Anticipate risks and gray areas as much as possible to obtain more precise results. For example, are departures of team members expected? Will they have a significant impact on your process?
Step 4: Together, Estimate The Effort Required
The estimation of story points is based on team discussions and is often done using a card game: Planning Poker or Scrum Poker.
During a game:
- Employees familiarize themselves with the selected user story and its objectives.
- Then they estimate, anonymously, the efforts to be made. To do this, everyone selects from their deck of cards the one with the most appropriate value.
- Participants then reveal their cards. If they match, then the final estimate is found. But if they diverge, each team member argues about their choices.
- Then, the estimate is repeated after discussion until a consensus is reached. Your business history provides valuable data to make a more accurate and credible story point assessment by comparison. So if you’ve done a similar project in the past, use the information about your previous performance to make new estimates.
Step 5: Set The Final Deadlines
Once the number of story points has been defined, it is time to set the deadlines for realizing the user scenario. To do this, determine the speed at which each contributor can execute a single story point. Let’s take the example of a task assigned a total value of 100 story points. An experienced member of the team will achieve a point in 2 hours. On the other hand, a junior will take 3 hours.
If the task responsibilities are divided equally between these two collaborators, then the estimate can be converted into hours in this way: 50 SP x 2 hours + 50 SP x 3 hours = 250 hours Thanks to this calculation, it then becomes possible to establish with precision the execution time of the user story. You now know all the secrets of story points.
However, to use this technique correctly, learning and training are required. But the rewards are worth it, as story points offer the opportunity to get more accurate and less rigid estimates and to rethink your approach to project management for the benefit of your team members and the company in his outfit.
Read Also: What Is A Project Manager?