The 7 Wastes of Lean, sometimes referred to as the 7 Wastes of Manufacturing were developed by Taiichi Ohno, the “father” of the Toyota Production System. It represents seven inefficient activities that don’t add value to the company, the Muda. The 8 Wastes of Lean is an extension of this philosophy, keeping the original seven wastes identified by TPS, but including an eighth waste of non-utilized talent.
A great way to remember the 8 Wastes of Lean is with the Lean acronym DOWNTIME, with each letter representing a form of waste:
- Defects: Products or services that don’t meet company standards are considered defective. Defective products will likely need to be thrown out or reworked, costing the company both time and money.
- Overproduction: Manufacturing more products than needed is wasteful. It can interfere with a smooth workflow, hide defects in the inventory, drives up storage costs, and result in a longer lead time. In addition, when a customers’ needs changed, a company can be left with a large amount of inventory that will not sell.
- Waiting: The time when a product is not actively being processed or transportation, it is waiting. Idle time between processes or time the manufacturing process is at a standstill makes for an inefficient and imbalanced production system.
- Non-Utilized Talent: This is the newest addition to the list of wastes, but an important one. It occurs when the expertise, experience, and skill of employees are not utilized. Managers can often times overlook the important input of workers and it results in a stale and wasteful manufacturing process. A facility will be much more efficient when employees feel comfortable giving suggestions and are given the opportunity to thrive in the workplace.
- Transportation: Any unnecessary movement of products fall under the category of transportation waste. It increases the risk of materials and products being damaged, can make unnecessary work, and is ultimately a waste of time and resources.
- Inventory: In this sense, inventory includes raw materials, work-in-progress, and finished goods that are not yet sold. The longer inventory sits in one of these phases of manufacturing, the more waste it creates. It can interrupt a smooth workflow and hide defects.
- Motion: This waste can sometimes be confused with transportation, but motion represents unnecessary movement during the manufacturing process. Some examples include workers straining themselves or equipment wear and tear.
- Extra-Processing: It’s important to understand the needs of the customer and what they want in a product. Over-processing is adding features to a product that are costly or time consuming and is ultimately not a customer requirement.