What is Lean Manufacturing? 5 Principle, Lean vs. Six Sigma

What is Lean Manufacturing? 5 Principle, Lean vs. Six Sigma

Lean manufacturing, sometimes abbreviated as “Lean,” is a production philosophy and system that emphasizes streamlining processes to reduce waste and increase efficiency. It is now a commonly used strategy in many different industries, helping to lower costs while boosting output and improving product quality. In this talk, we’ll go over the fundamentals of lean manufacturing, contrast it with Six Sigma, and examine the main elements that contribute to lean’s effectiveness.

“Lean manufacturing is an approach that aims to minimize waste within manufacturing systems while maximizing productivity. Waste, in this context, is defined as anything that customers do not perceive as adding value and are unwilling to pay for.”

Principles of Lean Manufacturing

Lean manufacturing is built upon several fundamental principles, each of which is designed to drive continuous improvement and create value for both customers and the organization. The five core principles of Lean manufacturing are:


Lean’s main goal is to provide value to the consumer. Organizations must determine and describe what the client considers valuable in order to do this. This entails being aware of the preferences and demands of the consumer and making sure that the goods and services meet their needs. Customers will pay for anything they perceive as having value, and Lean manufacturing focuses on getting rid of any activities or processes that do not directly contribute to this perception of value.

Value Stream

Identifying the whole value stream, which includes all the activities, procedures, and resources needed to deliver the value to the customer, comes after the value has been defined. This entails charting the movement of labor, supplies, and information during the whole manufacturing process. Organizations can find opportunities for improvement, redundancies, and bottlenecks by visualizing the value stream.


Lean emphasizes the need for a continuous flow of work without interruptions or delays. The aim is to streamline processes to ensure that products and services move smoothly from one step to the next, minimizing lead times and reducing waste. Achieving flow requires the elimination of unnecessary work-in-progress (WIP), optimizing workstations, and maintaining a consistent production pace.


In Lean, the production process is driven by customer demand. Instead of producing products based on forecasts or stockpiling inventory, organizations operate on a pull system. This means that work is only initiated when there is a demand for it. Pull systems are more responsive to customer needs and reduce the risk of overproduction.


The pursuit of perfection is an ongoing process in Lean manufacturing. Continuous improvement is at the heart of Lean, and organizations are encouraged to relentlessly eliminate waste, reduce defects, and enhance efficiency. Perfection is an aspirational goal, and Lean organizations continuously strive for it.

Lean vs. Six Sigma

Lean and Six Sigma are two distinct methodologies, but they share common goals of improving processes and reducing defects. However, they approach these objectives differently. Here are some key differentiators between Lean and Six Sigma:



Lean primarily targets waste reduction and process efficiency. It aims to streamline operations and eliminate non-value-adding activities.

Six Sigma

Six Sigma focuses on reducing process variation and minimizing defects. It is highly data-driven and aims to improve quality by identifying and addressing the root causes of defects.



Lean employs various tools and techniques such as value stream mapping, 5S (Sort, Set in order, Shine, Standardize, Sustain), Kanban, and Andon to enhance process flow and eliminate waste.

Six Sigma

Six Sigma relies on the DMAIC (Define, Measure, Analyze, Improve, Control) or DMADV (Define, Measure, Analyze, Design, Verify) methodology to systematically improve processes and reduce defects.

Waste Reduction:


Lean explicitly targets the elimination of waste, categorizing it into seven types: overproduction, inventory, motion, waiting, transportation, over-processing, and defects (often remembered by the acronym TIMWOOD).

Six Sigma: While Six Sigma does address waste, its primary focus is on defects and reducing process variation. Waste reduction is an inherent part of improving quality.

Tools and Techniques:


Lean tools are designed to improve flow, such as Kanban for visual management and pull systems. It also includes tools for workspace organization, like 5S, and methods for continuous improvement.

Six Sigma

Six Sigma employs statistical tools and techniques, such as control charts and regression analysis, to measure and analyze process variation. It also uses tools like the Fishbone diagram (Ishikawa) and Failure Mode and Effects Analysis (FMEA) to identify root causes of defects.



Lean places a strong emphasis on delivering value to the customer by eliminating non-value-adding activities and optimizing processes.

Six Sigma

While Six Sigma benefits customers by improving product quality, its primary focus is on reducing defects rather than explicitly delivering value.



Lean can be integrated with Six Sigma in a complementary manner, creating Lean Six Sigma. This approach combines the waste-reduction capabilities of Lean with the defect-reduction and process improvement capabilities of Six Sigma.

Combining Lean and Six Sigma

Many organizations recognize the value of integrating Lean and Six Sigma to create a comprehensive approach to process improvement. This combined methodology, often referred to as Lean Six Sigma, leverages the strengths of both Lean and Six Sigma to maximize efficiency, reduce waste, and enhance quality. Lean Six Sigma projects typically follow the DMAIC or DMADV methodology while incorporating Lean tools to streamline processes and eliminate waste.

The integration of Lean and Six Sigma allows organizations to:

  • Improve process flow and efficiency.
  • Reduce defects and variations.
  • Minimize waste and non-value-adding activities.
  • Enhance product and service quality.
  • Increase customer satisfaction.
  • Achieve cost savings and higher profitability.
  • By combining these two methodologies, organizations can achieve a more holistic approach to process improvement, addressing both efficiency and quality simultaneously.


Lean manufacturing is a production philosophy centered on the principles of value, value streams, flow, pull, and perfection. It aims to eliminate waste, optimize processes, and deliver value to customers. While Lean and Six Sigma share common goals, they differ in their primary focus and methodologies. Lean concentrates on waste reduction and process efficiency, while Six Sigma emphasizes defect reduction and quality improvement. Organizations can integrate these methodologies to create a comprehensive approach to process improvement, known as Lean Six Sigma, which leverages the strengths of both Lean and Six Sigma to maximize efficiency, reduce waste, and enhance quality. Ultimately, the choice between Lean and Six Sigma, or the integration of both, depends on an organization’s specific goals and needs.