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With limited time and shifting demands, development teams need a systematic way to focus on high-impact work. That’s where Weighted Shortest Job First (WSJF) prioritization comes in.

WSJF provides a powerful framework for identifying and sequencing the most economically sensible tasks that can be finished quickly.

By considering factors like duration, value, delay costs, and risks, it offers a quantitative method for ranking items in the backlog.

Rather than relying on guesswork, Weighted Shortest Job First (WSJF) weighs metrics like business value, completion timeline, potential costs from delays, and risk levels.

This multifaceted analysis provides a rational, optimized plan for chipping away at the backlog.

The approach streamlines focus on work that offers quicker wins while delivering maximum customer benefit given constrained schedules and budgets.

WSJF brings structure to continuously accomplishing the most impactful work first.

Key Highlights

• Weighted Shortest Job First (WSJF) calculates an optimized priority score for backlog items factoring in duration, business value, delay costs, and more.
• By considering these economic aspects, WSJF helps teams focus on the most worthwhile work deliverable in the near term.
• This optimizes return on investment by accounting for the detriments of late delivery and missed opportunities.
• Aligned with lean methodology, WSJF’s goal is maximizing value while minimizing waste through intelligent sequencing.
• Numbers-driven prioritization empowers planning informed by metrics like opportunity cost and delay penalty.
• Weighted Shortest Job First guides prioritizing what offers the greatest short-term benefit versus a purely subjective view.
• This collaborative, data-based technique puts valuable products and features at the forefront to best satisfy customers amid resource constraints.

What is Weighted Shortest Job First (WSJF)?

Rooted in lean principles and critical chain theory emphasizing minimized waste and maximized value, WSJF provides a structured method for prioritizing work.

By incorporating metrics like delay expenses, timeframe needs, and other salient factors, Weighted Shortest Job First (WSJF) ensures teams focus initially on the most crucial, time-sensitive deliverables.

This approach proves particularly useful under limited resources or competing priorities, aiding objective selection of projects to prioritize.

Quantifying each item’s importance aligns efforts with business goals. WSJF maximizes ROI and efficient value conveyance to customers.

At its core, Weighted Shortest Job First prioritizes items based on potential financial impact per time required. This yields a numerical score ranking tasks. Higher scores indicate higher urgency.

Calculation of prioritized scores supports a well-informed selection of the options affording the greatest near-term advancement versus a subjective view. Collaboratively data-driven, WSJF elevates what best serves customers amid constraints.

Calculating WSJF

The Weighted Shortest Job First (WSJF) model uses a simple formula to calculate a priority score for each item or project in your backlog. This score allows you to rank and prioritize work based on the cost of delay, job duration estimates, and other factors.

The WSJF formula is:

WSJF = (Cost of Delay / Job Duration) * (Prioritization Factors)

Cost of Delay is an estimate of the potential economic impact or opportunity cost of delaying the item or project. A higher cost of delay equates to higher priority.

Job Duration estimates how long the job will take to complete once work begins, usually measured in ideal days or story points.

Prioritization Factors are any additional criteria used to prioritize, such as risk, strategic alignment, dependencies, etc. This allows you to weigh the WSJF score based on other business priorities.

To calculate Weighted Shortest Job First (WSJF):

1. Estimate the Cost of Delay for the item/project if it were delayed indefinitely. This can be based on potential revenue, customer impact, strategic impact, etc.
2. Estimate the Job Duration required to complete the work.
3. Determine any Prioritization Factors to include and their relative weightings.
4. Plug the values into the formula to get the WSJF score.

Items with higher WSJF scores should be prioritized higher in the backlog. The formula quantifies the economic impact and opportunity cost of working on that item next versus delaying it.

This data-driven prioritization helps maximize return on investment (ROI) by focusing critical resources on the highest value, shortest job first.

Calculating WSJF scores across your backlog can objectively surface the most impactful work to tackle next.

Cost of Delay and Weighted Shortest Job First (WSJF)

The cost of delay is a critical concept that underpins the weighted shortest job first (WSJF) prioritization model.

Cost of delay represents the potential economic impact of delays in implementing a particular piece of work or project.

It aims to quantify the cost of not doing that work right away in terms of missed revenue opportunities, increased expenses, erosion of business value over time, and other factors.

In Weighted Shortest Job First (WSJF), the cost of delay is one of the key inputs used to calculate the prioritization score for each piece of work. A higher cost of delay means that work should be prioritized to minimize the economic impacts of delaying it.

The cost of delay directly factors into the numerator of the WSJF calculation, along with estimates of the work’s business value or user-derived value.

Properly evaluating the cost of delay is critical for effective WSJF prioritization. Teams need structured approaches to estimate the potential revenue impacts, customer impacts, competitive impacts, and other factors that contribute to the cost of delay metric. This analysis requires input from business leaders, product experts, and those closest to customer needs.

The cost of delay analysis provides an economic lens for prioritization, rather than relying solely on qualitative judgments of project “importance”.

By quantifying delay costs, Weighted Shortest Job First helps organizations maximize economic returns and business agility by systematically elevating the highest value, highest risk projects to the top of priority queues.

Common cost of delay factors include:

• Missed revenue/business opportunities 
• Potential customer churn/loss
• Competitive threat mitigation
• Regulatory compliance risks
• Technical debt and architectural issues
• Operational inefficiencies

Incorporating robust cost of delay evaluation is key to realizing the benefits of the WSJF prioritization model. It aligns project priorities with overarching business drivers and economic impacts.

Weighted Shortest Job First (WSJF) in Agile and Lean Environments

The weighted shortest job first (WSJF) model aligns perfectly with agile and lean principles that prioritize delivering maximum customer value in the shortest amount of time.

Agile emphasizes responding to change, continuous delivery, and close collaboration with customers. WSJF helps agile teams objectively prioritize the highest-value items that can be completed quickly.

In lean product development, the focus is on minimizing waste and optimizing flow. WSJF allows lean teams to calculate the economic impact of delay for each item and prioritize the jobs that will minimize that cost of delay.

This prevents expensive work from being started prematurely before the most critical items are completed.

Weighted Shortest Job First (WSJF) helps agile and lean teams make prioritization decisions based on quantitative data rather than subjective opinions or hierarchical priorities.

The formula captures the key tradeoffs of value vs effort that teams face every sprint. Using WSJF, backlog grooming, and reprioritization becomes an objective, data-driven exercise.

For projects using agile methods like Scrum or Kanban, WSJF can prioritize the product backlog at the epic or feature level.

As requirements become clearer during sprints, WSJF can further prioritize user stories within each prioritized feature.

This progressive elaboration allows long-term roadmaps to be mapped while still allowing short-term priorities to be continually optimized.

In lean development, WSJF aligns with practices like Set-Based Concurrent Engineering which explores multiple options before committing to a final design.

The formula’s focus on short lead times prevents teams from overcommitting to large work items before validating assumptions.

Overall, the weighted shortest job first framework complements agile and lean philosophies by quantifying priorities, maximizing economic outcomes, and enabling frequent course correction based on current conditions.

It allows these methodologies to scale effectively to complex product portfolios.

Advanced Considerations

While the basic WSJF calculation provides a good starting point for prioritizing work, some additional factors experienced teams may want to account for in their prioritization.

Risk Factors

Some initiatives carry more risk than others due to technical complexity, organizational barriers, or other uncertainties.

Teams can choose to factor in a risk component to the WSJF calculation to help prioritize lower-risk items. This could take the form of a multiplier that increases the score for lower-risk items.

Dependencies 

In many cases, initiatives have dependencies on other pieces of work being completed first. Strict Weighted Shortest Job First (WSJF) prioritization may suggest starting with items that are blocked by other initiatives.

Teams should analyze dependencies and prioritize accordingly, potentially re-ordering the backlog based on dependencies after the WSJF scores are calculated.

Strategic Alignment

While the WSJF looks at economic factors, there may be strategic goals or focus areas that a team or organization wants to prioritize, even if the direct economic benefit is lower.

Teams can consider adding a strategic alignment component to influence prioritization toward these key areas.

Resource Availability

The basic WSJF doesn’t account for resource capacities or constraints.

If certain initiatives require very specific skills that have limited availability, that may impact their true “duration” and how soon they can realistically be scheduled. Teams should analyze resource forecasts when doing prioritization.

Time Criticality  

Some initiatives may be time-sensitive, with a risk of the economic value degrading if they are not executed within a certain timeframe.

Teams can account for this time criticality, potentially boosting the CoD values for time-sensitive items.

By considering these more advanced factors along with the core WSJF calculation, teams can further refine their prioritization to ensure they are optimizing for both economic outcomes and real-world constraints and objectives.

However, it’s important not to make the prioritization model too complex, as that can defeat the original purpose of using a quantitative prioritization approach.

Best Practices and Tips for implementing Weighted Shortest Job First (WSJF)

When implementing the weighted shortest job first (WSJF) model, there are some best practices to keep in mind to get the most value out of it.

Align WSJF with Company Goals

Make sure the factors used to calculate WSJF (cost of delay, job duration, etc.) are aligned with your company’s overall strategy and objectives.

The WSJF model is meant to prioritize work that delivers the highest value, so adapt it to what “value” means for your business.

Get Buy-In From Stakeholders 

Having a transparent prioritization framework like Weighted Shortest Job First (WSJF) can be a shift from traditional methods. Get buy-in from key stakeholders, leadership, product teams, etc. by explaining the WSJF approach and its benefits.

Start With a Pilot

Don’t try to apply WSJF to every project right away. Start with a pilot on one product line or team first. Use it as a test case, get feedback, and refine the process before scaling it more broadly.

Train Teams on WSJF

Ensure all teams understand the WSJF concepts and calculations. Provide training, examples, and make sure there is consistency in how job estimates and other inputs are derived.

Use Data Over Gut Feelings

While the WSJF model allows for some subjectivity, rely on objective data as much as possible rather than gut instincts.

For example, use market research to estimate job value rather than opinions.

Regularly Review and Update

The inputs for WSJF calculations can change over time. Build in regular reviews (monthly, quarterly, etc.) to update values like the cost of delay, job size, priorities, etc. as situations evolve.

Complement With Other Techniques

Weighted Shortest Job First (WSJF) is meant for higher-level prioritization. Use it in conjunction with other prioritization techniques like story mapping or value vs. effort scoring for prioritizing within a job/project.

By following these tips, teams can get the most value and accuracy out of implementing the weighted shortest job first prioritization framework. It takes some upfront effort but can pay dividends in better resource allocation.

Conclusion

The Weighted Shortest Job First (WSJF) model provides a powerful prioritization framework for product teams to maximize economic impact and ROI.

By quantifying the cost of delay against job duration and other factors, WSJF helps cut through subjective opinions and make data-driven decisions on what to work on next.

While simple in concept, WSJF requires disciplined implementation of the prioritization process. Teams must take care to accurately estimate parameters like job duration, value, and cost of delay.

Using WSJF effectively also requires a deep understanding of customer needs, market conditions, and business strategy.

As with any prioritization technique, WSJF has its limitations. It works best for initiatives with relatively well-understood scopes and economic impacts.

Other prioritization frameworks may be more suitable for exploratory projects with highly uncertain outcomes.

Weighted Shortest Job First (WSJF) is a powerful tool that aligns well with lean and agile principles of maximizing value delivery and minimizing waste.

Focusing teams on the highest value: shortest time ratio items drives faster ROI and business impact. For product organizations wanting a data-driven prioritization process, WSJF is certainly a model worth evaluating.