The Wastes of Lean

Taiichi Ohno, the pioneer of the Toyota Production System, formally identified common wastes found in manufacturing and coined it as the 7 Wastes of Lean. The 8 Wastes of Lean is simply an extension and update of Ohno’s original philosophy. Lean manufacturing breaks down different categories of waste: Muda, Mura, and Muri. Literally translated from Japanese, Muda means useless, and the original 7 Wastes of Lean fall under this category of the 3M’s.

What are the 7 wastes of Lean?

The seven wastes commonly found in workplaces are not industry specific and can be found in nearly any facility. The identified seven wastes are as follows:

  1. Defects in the end product: This refers to any product or service that does not meet company standards. Defects as waste often require reworking to become sellable or are scrapped entirely.
  2. Waiting between processes: It can be easy to overlook the waste of waiting, but it is an important one. This refer to the downtime between steps in a production process. The result of excess waiting is often overproduction.
  3. Non-essential movement: When people or equipment are moving more than necessary, it results in the waste of motion. Extra movement can expend too much energy and increase the risk of an accident.
  4. Excess inventory: Having too much inventory on hand is wasteful and is typically a result of over-purchasing or excessive production. An excess amount of inventory can lead to defected or damaged products, longer lead time the production process, an inefficient use of capital.
  5. Excessive production: Overproduction occurs when a product (or a piece of it) is created before customer demand requires it. It often results with interrupted workflow, a higher storage cost, hidden defects in inventory, and more.
  6. Redundant processes or extra processing: There can be a variety of things that count as extra processing. It could be using equipment beyond required capacity, over-engineering a soliton, or spending too much time on unnecessary analysis.
  7. Unnecessary transport or handling of materials or products: This waste is often the most difficult to spot and is the unnecessary movement of materials during the production process. It can often lead to defective products and a loss of time.

What is the eighth waste of Lean?

The newest addition to the lists of waste is non-utilized talent, also referred to as the waste of human talent. Although it is not formally acknowledged by the Toyota Production System, it is important for companies to consider this waste. When managers don’t properly train employees or utilize their expertise, experience, and skill. It results in the waste of non-utilized talent. Properly trained workers and workers with their voice heard will make the whole production more efficient.

How to reduce wastes

Although some of these wastes can seem small, they can cost your company both time and money. Fortunately, Lean offers several tools a business can use to address these kinds of wastes. Utilize tools like Takt time, Kanban, or Six Sigma to address the wastes in your facility.

Additional Resources