Increase efficiency in your facility with Lean tools and techniques.

What is Waste of Lean?

Even the most technologically advanced manufacturing companies often produce waste, which is a silent killer of profits, resources, and efficiency. Today’s consumers are more environmentally conscious, meaning that waste reduction is no longer just about saving costs. It’s about long-term company health, product quality, customer satisfaction, and commitment to sustainability.

The Lean Manufacturing approach identifies eight key areas where waste occurs and provides strategies to eliminate them. This approach enables manufacturers to optimize operations, reduce environmental impact, and ultimately achieve lasting success.

This article will explore the eight types of waste lean commonly found in manufacturing processes. We’ll also examine how implementing specific Lean principles can help your organization identify and eliminate these wastes within your own operations.

What Is The Origin Of Waste?

The concept of lean waste manufacturing can be traced back to the Toyota Production System (TPS), developed by Taiichi Ohno in post-war Japan. Faced with limited resources and a need for efficiency, Ohno identified seven areas where activities did not directly add value for the customer. These areas, known in Japanese as “muda,” or “wastefulness,” became the foundation for eliminating unnecessary steps and streamlining production processes.

Over time, as Lean principles spread beyond Toyota, an eighth waste was added: “non-utilized talent.” This waste acknowledges the importance of employee skills and knowledge, and the need to utilize them effectively to achieve optimal results. Today, these eight wastes remain a cornerstone of Lean manufacturing, helping organizations identify and eliminate inefficiencies, ultimately leading to a more productive and sustainable operation.


TIMWOODS is a mnemonic acronym used in Lean manufacturing to identify eight categories of lean waste within a production process. These wastes represent activities that consume resources but do not directly add value for the customer. By understanding and eliminating these lean manufacturing wastes, companies can achieve significant improvements in efficiency and cost-effectiveness.

Here’s a breakdown of the eight wastes in TIMWOODS:

  • Transport: Unnecessary movement of materials, parts, or products within the production process.
  • Inventory: Holding excess raw materials, work-in-progress (WIP), or finished goods beyond what’s immediately needed.
  • Motion: Inefficient movements by workers during production, such as excessive bending, reaching, or walking.
  • Waiting: Idle time for workers or equipment due to delays in materials, instructions, or equipment availability.
  • Overproduction: Producing more goods than customer demand requires.
  • Overprocessing: Performing more steps or using more complex methods than necessary to create a product.
  • Defects: Any flaws or errors in products that require rework or lead to scrap.
  • Skills underutilization: Failing to utilize the full knowledge, skills, and abilities of employees.

Let’s discuss about them in more detail:

  1. Transport

    Lean manufacturing identifies transportation waste as any movement of materials, parts, or products that does not directly add value for the customer. This includes unnecessary movement within a facility, as well as excessive transportation between different stages of the production process.

    Causes of Transportation Waste:

    • Poor Plant Design: Inefficient layouts with large distances between workstations can lead to excessive movement of materials.
    • Long Material Handling Systems: Overly complicated conveyor belts or inefficient routing of materials can contribute to transportation waste.
    • Large Batch Sizes: Producing large batches of products at once can require more transportation compared to smaller, more frequent batches.
    • Multiple Storage Facilities: Having materials stored in multiple locations can necessitate unnecessary movement when needed for production.
    • Poorly Designed Production Systems: Production processes that don’t consider the flow of materials can lead to backtracking and unnecessary movement.
  2. Inventory

    Inventory lean manufacturing waste refers to any raw materials, work-in-progress (WIP), or finished goods that are held in excess of what is immediately needed to meet customer demand.  While some level of inventory may be necessary for smooth operations, holding excessive inventory is considered wasteful because it represents tied-up capital, storage costs, and potential obsolescence.

    Causes of Inventory Waste:

    • Overproduction: Producing more goods than customer demand requires leads to a build-up of finished goods inventory.
    • Poor Forecasting and Planning: Inaccurate forecasting of customer needs or inefficient production planning can result in overproduction and excess inventory.
    • Broken Processes: Poor coordination between manufacturing, purchasing, and scheduling can lead to unnecessary safety stock, contributing to inventory waste.
    • Delays in Production (Waiting Waste): Production delays can cause raw materials and WIP to accumulate, creating inventory waste.
    • Inventory Defects: Defective products stored in inventory represent wasted resources and effort.
    • Excessive Transportation: Unnecessary movement of materials within the production process can inflate inventory levels.
  3. Motion

    Motion waste can significantly reduce productivity in manufacturing. In lean manufacturing, motion waste refers to the unnecessary movement of machinery or workers due to inefficient manufacturing processes. This type of waste can cause wear and tear on workers and machinery, reducing their lifespan or ability to work effectively. Motion waste in manufacturing refers to unnecessary and repetitive movements that do not add value to the customer, including repeatedly reaching for materials, walking to get a tool and having to readjust a component after it has already been installed.

    Causes of Motion Waste:

    • Poor Workstation Layout: Inefficient arrangement of workstations that restricts productivity and creates obstacles for workers.
    • Poor Production Planning: Poorly organized and coordinated production results in delays and setbacks.
    • Poor Process Design: Flawed or ineffective methods and processes that result in errors and wasted resources.
    • Shared Equipment and Machines: Multiple departments or individuals using the same equipment can lead to conflicts, delays and resource limitations.
    • Lack of Production Standards: Lack of established guidelines and benchmarks for quality, efficiency and consistency, resulting in variability and suboptimal results.
  4. Waiting

    “Waiting waste” in lean manufacturing refers to the time and resources that are wasted when workers or processes are idle or waiting for the next step in the production process. It is a form of inefficiency that reduces productivity and adds unnecessary costs to the manufacturing system. Waiting waste causes significant capital wastage in many businesses, which in turn increases costs throughout the organization.

    Causes of Waiting Waste:

    • Unplanned downtime or idle equipment: Unexpected equipment inactivity or non-operational time periods.
    • Not enough people: Insufficient workforce to handle the required tasks efficiently.
    • Long or delayed set-up times: Excessive time is taken to prepare equipment or machines for the next production run.
    • Poor process communication: Ineffective or inadequate exchange of information between individuals or departments involved in the production process.
    • Lack of process control: An absence or deficiency in monitoring and maintaining control over the production process results in delays.
  5. Overproduction

    Overproduction waste occurs when unnecessary parts, assemblies or products are produced or when items are manufactured before they are needed. This results in wasted time and resources that could be used more effectively. Additionally, it leads to unnecessary inventory waste due to overstocking of products. High production can also hide defects that could have been identified earlier if the work had been done at a more balanced pace. Early identification and removal of defects can reduce the amount of material waste.

    Causes of Overproduction Waste:

    • Inefficient production planning: Poorly organized production processes lead to excessive waste.
    • Lack of demand forecasting: Failure to accurately predict customer demand, resulting in surplus production.
    • Unstable production schedules: Inconsistent scheduling causes overproduction and waste.
    • Poor automation: Inadequate use of technology and automation leads to productivity limitations in production.
    • Poor communication and coordination: Lack of effective collaboration between departments leads to errors and overproduction.
  6. Overprocessing

    Overprocessing waste happens when unnecessary work is done than what is required by the customer, such as excessive inspections, redundant process steps, or using expensive equipment for simple tasks. This waste leads to financial costs in terms of staff time, materials, and equipment wear. Moreover, it can decrease the overall efficiency of your business as the operators who engage in overprocessing may waste their time and skills on tasks that do not add value to customers or generate revenue for the company.

    Causes of Over Processing Waste:

    • Poor Communication: Lack of effective information exchange leads to overprocessing waste.
    • Not Understanding Your Customers’ Needs: Failure to fully comprehend customer requirements, resulting in unnecessary work.
    • Human error: Mistakes made by employees leading to overprocessing and wasted effort.
    • Slow approval process or excessive reporting: Delays in approvals or excessive reporting requirements causing additional work that is not essential to meet customer needs.
  7. Defects

    Defects represent a significant waste in Lean manufacturing.  They encompass any flaws or errors in products that require rework, scrap, or replacements. Defects not only impact the quality of the final product but also lead to a series of negative consequences like increased costs, time delays, resource waste and reduced customer satisfaction.

    There are several causes that contribute to defects in a manufacturing environment:

    • Poor Quality Control: Inadequate quality control measures at various stages of production can allow defects to go undetected.
    • Poor Machine Repair: Equipment malfunctions or lack of preventative maintenance can lead to production of defective products.
    • Lack of Proper Documentation: Inconsistent or missing documentation on processes, procedures, and specifications can lead to errors during production.
    • Lack of Process Standards: The absence of well-defined and standardized work procedures can increase the likelihood of deviations and defects.
    • Misunderstanding Customer Needs: If product design or specifications don’t meet customer requirements, defects can occur.
    • Inaccurate Inventory Levels: Incorrect inventory management can lead to the use of outdated or faulty materials, resulting in defects.
  8. Skills Underutilization:

    This waste occurs when the knowledge, skills, and abilities of employees are not fully utilized within their roles or across the organization. In essence, skills underutilization represents a missed opportunity to leverage the full potential of the workforce.

    Common causes of this waste:

    • Mismatched Skills and Tasks: Assigning employees to tasks that don’t align with their skillset can lead to underutilization.
    • Limited Job Design: Rigid job descriptions with narrow responsibilities can prevent employees from applying their broader skillsets.
    • Lack of Training and Development: Employees may not have the necessary training or opportunities to develop new skills, hindering their ability to take on more challenging tasks.
    • Poor Communication: Inadequate communication between management and employees can prevent the identification and utilization of employee skills.
    • Silos and Knowledge Sharing Barriers: Organizational structures with limited cross-functional collaboration can create silos of knowledge and prevent the sharing of skills across departments.


Lean manufacturing’s focus on waste elimination equips companies with a powerful tool to optimize operations. By understanding and eliminating the eight types of waste lean of TIMWOODS, organizations can unlock significant benefits like improved efficiency, reduced costs, and enhanced customer satisfaction.

The journey to eliminate waste is ongoing.  Companies that foster a culture of continuous improvement and encourage employee participation in identifying and addressing waste are best positioned to achieve lasting success.  By minimizing waste, businesses can not only gain a competitive edge but also contribute to a more sustainable future.

Additional Resources