Lean vs. scrum

If your organization is looking for ways to work more efficiently, reduce wasted effort, and create better products or services, you may have come across the terms lean and scrum. These are two popular approaches to managing all sorts of complex work.

In the broadest terms, lean is a philosophical approach to work that reduces wasteful efforts and improves efficiency, while scrum is a lightweight framework for delivering value incrementally. 

Many companies practice both lean thinking and the scrum framework. You don’t have to pick one over the other. When used effectively, they can help your teams respond to changes quickly, reduce unnecessary work, and stay motivated. 

What is lean?

Lean is a way of working that focuses on eliminating waste (any activity that doesn't add value) and improving efficiency. It originated in Toyota’s manufacturing processes in the 1950s as a way to produce high-quality cars while reducing unnecessary steps. Since then, businesses in many industries—including software development, sales, and healthcare—have adopted lean principles to improve their operations.

The five key principles of lean

There are many ways to define the key principles of lean manufacturing, but people often point to the 2003 representation by James Womack and Daniel Jones in the book "Lean Thinking," which conceptualizes the lean system as being based on five key principles—

1. Define value: Focus on what is truly valuable to the customer.
2. Eliminate waste: Remove steps that do not add value to the final product or service.
3. Create a smooth flow: Ensure work moves efficiently through each stage.
4. Establish a pull system: Only produce work when it is needed, reducing excess inventory or effort.
5. Continuously improve: Regularly refine processes to maximize efficiency.

In software development and other industries, lean encourages teams to:

• Avoid unnecessary work
• Make decisions based on the latest available information
• Deliver results quickly and refine them over time
• Empower employees to make decisions
• Focus on the big picture rather than isolated tasks

Rather than imposing strict rules, lean provides guiding principles that teams can adapt to their specific needs.

What is scrum?

Scrum is a structured—albeit lightweight—agile framework designed to help teams break down complex problems into manageable slices of work and deliver incremental value over time. Contrast it with a traditional waterfall project management approach, in which phases like requirements gathering, design, implementation, testing, and deployment are carried out in a cascade, one after the other. 

Scrum is based on a clear set of team accountabilities (roles within a team), events, and artifacts.

How scrum works

Scrum breaks work into short, focused cycles called sprints, which usually last between two to four weeks. Teams plan, execute, and review their work in these cycles, allowing for continuous improvement and faster delivery of results.

Key roles in scrum

• Scrum master: Facilitates and coaches the scrum process, manages impediments, and fosters continuous improvement.
• Product owner: Represents customer needs and orders work based on business value.
• Developers: The team members responsible for executing tasks and delivering the product.

Key events in scrum

Scrum teams work in timeboxed iterations called sprints, during which they focus on delivering a set of product backlog items. This selection becomes the sprint backlog. Within each sprint, there are four key events:

1. Sprint planning: The team decides what work to complete in the upcoming sprint.
2. Daily scrum: A quick check-in to discuss progress and roadblocks.
3. Sprint review: A meeting to showcase what has been accomplished.
4. Sprint retrospective: A time to reflect on what went well and what can be improved.

Key artifacts in scrum

Scrum includes several key artifacts that help teams manage their work effectively:

1. Product backlog: Managed by the product owner, the backlog is a dynamic, ever-changing list of work items that need to be completed on the path to the product goal.
2. Sprint backlog: A subset of the product backlog that the team forecasts they can complete during the sprint.
3. Increment: The sum of all completed backlog items at the end of a sprint, representing increments of value.

These artifacts provide transparency and ensure that the team is always working on the most valuable tasks.

Scrum helps teams create a predictable, iterative development cycle that encourages transparency, adaptability, and customer feedback. Though initially designed for software development, scrum has since been adopted in industries as diverse as construction, healthcare, and even automotive manufacturing, including Toyota, the pioneers of lean.

How lean and scrum work together

Lean and scrum share the same goal—helping teams work smarter, but they achieve it in different ways.

Key differences:

1. Structure: Lean is a flexible philosophy, while scrum follows a structured framework with defined accountabilities and events.
2. Process improvement: Lean encourages continuous improvement without specific scheduled events. Scrum builds process improvement into the framework through sprint retrospectives.
3. Decision-making: Lean teams make decisions as late as possible to use the most up-to-date information. Scrum teams break work into small pieces and adjust in each sprint cycle.
4. Flexibility: Lean teams focus on refining existing workflows, while scrum teams follow an iterative process with structured cycles.

How they complement each other

• A scrum team might apply lean principles to optimize its workflow and eliminate unnecessary work.
• A lean organization might incorporate scrum's structured events to improve team collaboration and accountability.

By combining lean's focus on efficiency with scrum's iterative value delivery, teams can create a work environment that is both productive and adaptable.

How to choose the right approach for your teams

If you're thinking about transforming the way you do things at your organization with lean or scrum, think about your current challenges and goals:

• If your team needs more structure and clear roles, scrum might be a better fit.
• If your team values flexibility and wants to refine existing processes, lean could be the right choice.
• If you want to blend structure with efficiency, using scrum with lean principles can offer the best of both worlds.

The most important thing is to experiment and adapt. Many teams start with one approach and incorporate elements of the other as they evolve.

The path to continuous improvement

Lean and scrum are both effective ways to help teams work more efficiently, adapt to changes, and continuously improve. Lean helps teams eliminate waste and focus on delivering value, while scrum provides a framework for team collaboration and iterative development. Rather than choosing one over the other, consider how combining these approaches can help your team work smarter, innovate faster, and stay engaged.

By understanding and applying lean and scrum in a way that fits your team, you can create a more productive and rewarding work environment.

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Whether you're a manager, team leader, or individual contributor, Scrum Alliance has specialized, focused microcredential courses designed to build skills and knowledge in both lean and scrum. Take a microcredential course today to grow and showcase your knowledge with a lifetime microcredential badge.

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