What Is Lean, Six Sigma, and Lean Six Sigma?

What is Lean Six Sigma? 

In this post, we’ll learn what Lean Six Sigma is, how it’s different from Six Sigma, how it’s different from lean methodologies, and why this business methodology has become so popular.

What Is Lean Six Sigma?

To better answer the question “What is Lean Six Sigma?” We should note that Lean Six Sigma is a combination of two other methodologies: lean and Six Sigma. 

Below we’ll look at each of these in detail, and then describe how and why they have been combined into Lean Six Sigma.

Lean 101

Lean is a business and a process improvement methodology that began in manufacturing, but it is since spread to many other areas of business. Today, lean is used not only in manufacturing, but also in management, product development, business development, and more.

Here are a few of lean’s key principles:

• Continuous improvement. One of the central pillars of lean is the idea that business processes should be constantly improved. Doing so will help achieve other goals important to this methodology, such as enhancing customer value and reducing waste. By continually improving processes, quality, products, and services, lean practitioners can continuously add more value to customers and the business.
• Reducing waste. Lean views waste as activities that do not add value to the customer. For example, developing products, features, or services that are irrelevant to the customer will end up adding no value to the customer or the business. The result: wasted effort, time, and resources.
• Enhancing customer value. Value refers to anything the customers willing to pay for to achieve satisfaction. The goal of lean, therefore, is to add as much value to the customer as possible. The logic is that by adding value to the customer, the business will perform better by default.

Lean can be broken down further, these are three of its most fundamental ideas. 

By applying and embedding ideas such as these into the business,  organizations throughout the world have seen major improvements. 

That being said, it is only one of many process improvement methodologies. 

It is also not 100% perfect – there are other methodologies that also aim to enhance customer success, but they take different approaches to achieving the same goal. 

One of those is Six Sigma.

Six Sigma 101

Six Sigma is a business methodology designed to improve business processes and outcomes, much like lean. Unlike lean, however, it does not focus on reducing waste.

Instead, it focuses on:

• Reducing defects. Defects in products and services affect customer value, profits, the organization’s performance in the marketplace, and more. Reducing these defects, therefore, is one of the main goals of Six Sigma.
• Applying a repeatable method to improve processes. DMAIC is an acronym that stands for define, measure, analyze, improve, and control. this approach is similar to the Plan-Do-Study-Act cycle, or PDCA. Both approaches are designed to be applied continuously in order to achieve the aims of Six Sigma, such as reducing defects and reducing process variation.
• Reducing process variation. While lean focuses on reducing waste in processes, Six Sigma aims to reduce variation in processes. This can enhance practitioners’ control over the quality and the outcomes of those processes.

Both of these business improvement methodologies have much in common, but they do have slightly different emphases. 

Six Sigma, for example, tends to focus more on statistical analysis, data, hypothesis testing, and similar scientific approaches. The end result, however, tends towards the same direction: greater customer value.

 Lean Six Sigma 101

Lean Six Sigma, unsurprisingly, integrates both of these methodologies into a single approach, in order to extract the best from each.

This approach emphasizes

• The principles of lean, such as reducing waste, improving efficiency and applying methods built around continuous improvement
• The core tenets of Six Sigma, such as reducing process variation and reducing defects
• The principles comment to both, such as customer satisfaction and bottom line profits

There are differences between the systems, of course. Lean Six Sigma for instance, prefers preventing defects to detecting them. Also, the application and focus of the DMAIC process will differ between Lean Six Sigma and Six Sigma.

Which Is the Best System for Your Organization?

Each methodology has merit. 

It would be therefore difficult to claim that one is universally better than the other. Instead, it is better to view each system in the context of one’s own needs.

An organization that wants to implement continuous improvement – without applying statistical methods and detailed analyzes such as those within Six Sigma – may prefer lean.

On the other hand, an organization that is highly data-driven and wants to use a method based around data, analysis, and statistics might find Six Sigma more useful.

Finally, a company that wants to combine both and extract specific features from each may choose Lean Six Sigma.

Where to learn more

There are several websites and resources available that discuss lean, Six Sigma, and Lean Six Sigma.

A few of these include:

• ASQ
• GoLeanSixSigma.com
• Our own articles on lean, Six Sigma, and Lean Six Sigma

Anyone truly interested in these methods, however, would need to do more then read online guides.Fortunately, there are a number of institutions that offer training and certifications in Lean Six Sigma, such as Purdue and GoLeanSixSigma, mentioned above.