Weighted Shortest Job First (WSJF)
What is Weighted Shortest Job First (WSJF)?
Weighted Shortest Job First (WSJF) is a prioritization technique used in product management that calculates what should be worked on first based on how quickly or easily the job can be done and how much it would cost the business to delay it.
The purpose of WSJF is to maximize economic value by considering how much time or effort it job takes, how urgent it is, the risks involved, and the opportunities it could open up.
WSJF can help to ensure that you complete valuable work first, reducing the cost of delay and enabling faster time-to-market for crucial features. According to Scaled Agile, the team behind the WSJF approach and SAFe, the point is to help you with “picking the next best job to do”.
It is an extension of the Cost of Delay framework and is also known as ‘Cost of Delay Divided By Duration’, or ‘CD3’.
How do you calculate WSJF?
To calculate WSJF, you use the following formula:
WSJF = (User-Business Value + Time Criticality + Risk Reduction + Opportunity Enablement) / Job Size or Duration.
- User-Business Value measures the economic impact a job will have on the organization or the customer.
- Time Criticality represents the importance of delivering the job within a specific time period.
- Risk Reduction denotes the level of risk reduction a job provides.
- Opportunity Enablement measures the potential business opportunities that completing the job might unlock.
- Job Size or Duration quantifies the effort or time required to complete the job.
By prioritizing features on their product roadmap using WSJF, Agile teams can prioritize the most valuable and time-sensitive tasks.
This approach also helps to align product managers, product owners, and development teams, ideally resulting in improved customer satisfaction, swifter economic benefits for their work, and more efficient product delivery.
However, WSJF has a number of drawbacks, so is best used as part of your prioritization tool-kit rather than being the only model you use.
For a breakdown of all of the prioritization frameworks that you’ll need to really nail being a product manager, including Cost of Delay, WSJF, and 15 more models, take a look at our incredibly helpful eBook The Product Manager’s Guide to Prioritization Frameworks.
How do you use WSJF?
WSJF provides a structured approach to prioritize initiatives based on their potential value, time criticality, risk reduction, and opportunity enablement.
Marketing teams and product teams can particularly benefit from applying WSJF to ensure they are focusing on the most impactful projects.
For product teams, WSJF aids in prioritizing product backlog initiatives or features. By considering the value of each feature, product professionals can leverage WSJF to identify those with the highest potential impact.
This allows product managers and development teams to focus on delivering features that align with customer needs, generate economic benefits, and enable business growth.
This approach can also help marketing teams to optimize resource allocation and deliver high-impact campaigns or initiatives.
How do you apply Weighted Shortest Job First?
Weighted Shortest Job First is commonly used in Agile and Lean environments to help teams make informed decisions about what work should be done next. It is based on the concept that the most valuable and time-critical jobs should be given the highest priority.
Here are the steps to apply WSJF:
1. Define the values of the factors involved
Start by assigning values to the factors involved in WSJF calculation. As detailed above, these are User-Business Value, Time Criticality, Risk Reduction, and Job Size or Duration. Determine the value of each factor based on the specific needs and goals of your organization or team.
Establish a set scale for each factor. This could be from one to 10, but the most important thing is that everyone involved is aware of how the values are determined and that they are assigning them in the same way.
Take a look at our glossary page on the Cost of Delay for guidance on how best to assign values for each of the factors that make up CoD.
2. Determine the Cost of Delay
The Cost of Delay (CoD) is established by adding together the values you’ve assigned to each of the factors mentioned in the previous step.
3. Estimate the size or duration of the job
You will again need to establish an agreed-upon scale for determining how big or time-consuming each job is. This can be difficult to establish accurately and depends on the particular demands of your business.
When determining your scale, keep in mind that lower-numbered jobs will be assigned a higher priority under WSJF.
4. Calculate the WSJF score:
To calculate the WSJF score, divide the Cost of Delay by the size or duration of the job using the formula:
WSJF = (User-Business Value + Time Criticality + Risk Reduction + Opportunity Enablement) / Job Size or Duration
5. Prioritize based on WSJF scores
Arrange the features in descending order based on their WSJF scores. This prioritization will help identify the most valuable and time-critical features that you should work on first.
For example, let’s say Feature A has a User-Business Value of 8, Time Criticality of 7, Risk Reduction of 5, and Job Duration of 3. Plugging these values into the formula, the WSJF score for Feature A would be:
WSJF = (8 + 7 + 5) / 3 = 6.67
Now let’s say that Feature B has a User-Business Value of 4, Time Criticality of 2, Risk Reduction of 8, and Job Duration of 2. The score for Feature B would be:
WSJF = (4 + 2 + 8) / 2 = 7
Therefore, according to WSJF, you would be best off prioritizing work on Feature A.
What are the pros and cons of Weighted Shortest Job First?
WSJF brings several benefits to product teams and the overall product development process. It allows product managers and product owners to better prioritize their teams’ work towards features that will provide the biggest returns for the smallest outlay of time or effort. This enables them to focus on delivering the highest value and time-critical features first, resulting in improved efficiency and productivity.
However, there are some potential drawbacks to using WSJF. One main challenge is the subjectivity involved in assigning values to the different factors. Depending on the individual or team’s perspective, they may assign different weights to each factor, leading to discrepancies in prioritization. Even when everyone is on the same page, their interpretation of each factor can still lead to inconsistencies in the scoring process.
By understanding the pros and cons of the WSJF framework, as detailed below, you will be able to decide if this approach will be of benefit to your team. As with other frameworks, it generally works best in combination with other prioritization tools.
Weighted Shortest Job First has a number of benefits it can bring to your product team when applied effectively:
- It helps teams focus on delivering the highest value and time-critical features first.
- It ensures that the most valuable work is prioritized in a way that leads to increased customer satisfaction and potentially higher financial returns.
- It addresses potential risks early on by including risk reduction in the calculation, reducing the chances of costly delays or failure.
- It optimizes teams’ efforts by prioritizing working on smaller, more manageable tasks first, enabling faster delivery and shorter time-to-market.
- It helps teams avoid the “cost fallacy” and prioritize initiatives based on their true value.
- It ensures that high-value initiatives are not delayed in favor of lower-priority projects.
While it has its benefits, there are also some drawbacks to consider when using WSJF, including:
- It heavily relies on data and numbers, and can sometimes inaccurately reflect the different types of value brought by various features of initiatives.
- The subjective nature of the values assigned to each factor can result in different stakeholders weighing the importance or impact of the factors inconsistently.
- It is biased towards highly-visible and short-term projects. Prioritizing your product backlog solely based on job duration and risk reduction, risks overlooking longer-term and strategic initiatives.
- It may not account for the complexity and interdependencies of different tasks or projects.
Given both the benefits and drawbacks of the Weighted Shortest Job First approach, it is often best to use it as just one of your prioritization tools rather than it is the only framework that you use.
Don’t forget to take a look at our Prioritization Framework eBook to find the other tools you’ll need to get the most from your prioritization process.