Lean, Agile and Scrum: A Simple Guide [2025]

Introduction

Lean and Agile are two terms that have been rising in recent years among software development teams. The market has been using these concepts in practice for some time, but there is still a lot of confusion about the meaning of each of these terms.

Many people get to know the agile methods through SCRUM and get confused by mistakenly associating SCRUM with AGILE.

However, they serve different purposes and tasks, and that is why it is important to understand each one of them.

So what are the differences?

LEAN and AGILE are not exactly methodologies. The LEAN and AGILE principles are a basis that can be applied to different methods (e.g. SCRUM and Kanban), so it would be wiser to refer to them as philosophies.

Lean, Agile and Scrum concepts

Agile, Scrum and Lean are names that are already part of the day to day of several managers. And in this sense, knowing how to handle the differences between agile methodologies is fundamental so that the company can make the most appropriate choice for its profile. The concepts are often used by the top custom software development companies.

Whenever you talk about Agile methods, many associate it with those colorful post-its, which are stuck to a whiteboard when tasks are assigned and removed once completed. In fact, this is just one of many ways to conduct and apply Agile methodology in a project, team, business management, and product prototyping.

In general, the objective of Agile methods is to reach the goals through continuous, easy to measure processes, integrating the participants and the tools in a collaborative way, always remembering the needs of the final client and exchanging feedback so that everyone can always be on the same page. The iterativeness of Agile methodologies makes it pair greatly with the time & material billing model.

We have listed below the concepts of LEAN, AGILE and SCRUM, to better clarify their concepts, values, principles, and processes.

Lean Definition

Management philosophy inspired by Toyota system practices and results is characterized by a process structure where there is an attempt to minimize risk and waste while maximizing customer value. Lean is the foundation of Agile and can be perfectly applied across multiple business areas.

Agile Definition

Iterative philosophy focused on time that makes it possible to build a product incrementally, step-by-step, delivering it in smaller pieces. The main focus of Agile is to make processes more flexible and capable of adapting to change quickly and to bring all stakeholders together. Thus, the delivery of results becomes faster and starts to be made from Agile decision-making routines and communicated in a simple way.

In other words, Agile creates a work environment that adapts and embraces change quickly. A system of “prioritization” of what will be delivered is adopted and all steps are structured in a simpler way. In Agile, teams have more autonomy and work with a smaller number of members.

Integration is a key step since it facilitates the exchange of information and enables problem resolution with agility. Thus, everyone can act to achieve the expected goals.

Scrum Definition

Agile, incremental and iterative development method, documented in the Scrum framework, which is a set of practices, roles, events, artifacts, and rules designed to guide the team in the execution of the project.

Scrum is one of the most used methods in the IT environment. Thus, through lean teams, Scrum intends to give more agility to the execution of IT processes avoiding problems such as gaps, conflicts and lack of integration. In addition, Scrum seeks to create a solid division of roles.

There is the position of Product Owner (which acts as the point between the enterprise and the client), Team Member (related to the development team) and Scrum Master (responsible for managing the routines of all teams), for example.

The origin of Agile methods

The Agile methods are more than a set of rules or procedures, it is a way of thinking, almost a philosophy. Basically, the agile methods are based on 3 main aspects:

• Customer focus (which must be constantly consulted)
• Working with small incremental advances, called iterations
• Testing progress and validation before proceeding

Agile thinking proposes to organize productive efforts in order to generate value in advance, to facilitate adherence to changing requirements and to maintain constant and accurate visibility during the execution of a project. As a result of this thinking, organizations are able to significantly reduce the risk associated with product development and maximize return on investment.

In fact, Agile came out of the Agile Manifesto, an initiative by software developers who were tired of casting and unproductive methods for their industry.

We can say that the Agile method would be an “umbrella” under which are Scrum, Kanban, and other methodologies, with Lean, for example.

The Agile Manifesto was created by software developers who were tired of working under rigid corporate rules that were holding back their creativity and making the process bureaucratic and predictable.

Therefore, they created the manifesto for Agile development, which preaches 4 premises that establish what should be really valued:

• Individuals and interactions rather than processes and tools
• Software in operation rather than comprehensive documentation
• Collaboration with the client rather than contract negotiation
• Responding to changes more than following a plan

Although it was originally created for software development, the concept has been adapted and evolved to the development of any type of product or service.

The key is to stay focused on customer needs, test every stage of project evolution, and make changes if necessary, only to take one more step and add one more improvement to the product or service being developed.

Over the time, Agile began to be adopted in several areas, such as team and project management, product development and even so-called agile marketing management.

The objective of Lean methods

In fact, Lean came much earlier than the Agile Manifesto. It emerged in postwar Japan in automobile factories that wanted to be more productive.

It turns out that Lean projects are quite effective if they incorporate Agile concepts into their execution. After all, Lean means lean, without excess or waste, something that meets all that the Agile methodologies propose.

There are a number of Lean tools (such as the 5S and Just-in-time) that should be used to combat the 8 wastes that bring inefficiency and reduce productivity in companies.

See what these 8 wastes are:

1. Wait
2. Defect
3. Transport
4. Movement
5. Excess Inventory
6. Excess production
7. Unnecessary processing
8. Unused talent

Later, the Lean concept was adapted by Eric Ries in his famous book, Lean Startup.

Scrum – framework, not methodology

The Agile Scrum framework is more an evolution of previous methods and is also widely used in software development.

Scrum and Agile often get confused, but should not because Scrum is a framework tested and consolidated by the market to structure Agile development teams.

The main characteristics of Scrum are:

• Set up multidisciplinary teams
• Working as a team
• Create a list of tasks that must be fulfilled (backlog)
• Adopt a regular and daily feedback routine
• Organize for “sprints” of work, with determined time to finish

In this case, incremental iterations and customer validation are taken to their extreme, by some rules and procedures, here are some of them:

• Product Owner: a member of the team that must act as a supporter of clients and do everything to ensure that the project meets their interests.
• Scrum Master: responsible for compliance with Scrum procedures without deviations or shortcuts.
• Daily Scrum: a quick meeting in the morning, before starting work, so that everyone can discuss the challenges of the previous day.
• Sprint Review: The iterations in Scrum are divided into sprints. In a sprint review, everything that was implemented by the team members in that period is presented to the rest of the group.
• Sprint Retrospective: Planning the next sprint based on the learning acquired in the previous one.

As you have seen, Scrum is quite specific and well structured, but the important thing is to understand that, regardless of your workflow, there will be a more appropriate way to employ these methodologies or others, more suitable for your business.

Remember, in all of them the important thing is to stay true to the customer’s needs and make the tasks flow without unnecessary disruptions.

Lean, Agile and Scrum benefits

Regardless of the differences between these three terms, we can say that the benefits of adopting agile concepts are great.

When the organization reaches a certain level of maturity in Lean and Agile adoption, it begins to enjoy the benefits below:

• Reducing development and maintenance costs: By significantly reducing the incidence of bugs, effectively identifying risks and ensuring better assertiveness, it is possible to significantly reduce the cost of a project over its lifetime;
• Anticipation of return on investment: the proposed model is based on the frequent delivery of functional software, ready to be used in production. Combined with reliable prioritization and planning techniques, it is possible to extract value from the software delivered in the first development iterations;
• Productivity 2 to 3 times greater compared to traditional approaches: elimination of waste, reduction of complexity and improvement in the quality of the code allows a considerable increase in the productivity of the development team;
• Total control, visibility, and manageability of the development cycle: the process provides accurate information about the progress of projects at any time, enhancing management and enabling better decision making;
• Greater assertiveness and adherence: changes are always welcome and your project is constantly adapted to your business needs;
• Less uncertainty: short planning and delivery cycles, more assertive estimates, and a build with integrity at all stages of the development process make it possible to increase predictability and decrease uncertainty in software development;
• Better quality of the final product: the quality management processes that take place from the early stages of product design and through the entire development guarantee a final product with superior quality.
• Continuous improvement: in addition to being a resilient process that adapts to the needs of different types of projects, the proposed process is based on a continuous cycle of improvement, through retrospectives and methods of inspection and adaptation applied throughout the entire lifecycle of the project.