What is Waste?
Waste is anything within a process that is not absolutely required to complete the process. Actions within a process can be split into multiple categories, Value Added and Non-Value Added actions. Within Non-Value added actions, there will exist necessary and unnecessary waste.
Learn more about how to identify value and getting started with Lean on Drive Process Improvements by Getting Started with Lean.
- Necessary Waste: E.G. work that must be done to meet government and/or regulatory approvals or is difficult to duplicate. Take effort to minimize
- Unnecessary Waste: This type of waste adds no value to the product. Eliminate!
- Value Add: “Cutting chips” – adding direct energy into the production or processing of a product.
Value is defined as anything the customer is willing to pay for – anything else is waste. The objective of this resource is to help identify the types of wastes within a process for elimination. The eight wastes are: defects, waiting, transportation, inventory, motion, over processing, over production, and underutilized talent.
Not the worst waste, but depending how far along the product is in the production cycle can result in higher costs. A defect is any unacceptable deviation to the intended product design. Defects results in wasted time to inspect, evaluate, and disposition the non-conforming item. This disposition may include scrapping of the product, reworking the product, or best case, “Use as is”. Even for a “Use as is” condition, waste was created in man hours and waiting to determine the appropriate next steps.
Anything that is not in transport or is actively being processed is waiting. This is the time spent in que or on someone’s desk waiting for a previous task to be completed. This is a very common and under appreciated form of waste often caused by poor process flow, batch processing, and production time is less than the takt time.
Transportation refers to the moment of material from one location to another. This is often thought of as transportation within a manufacturing environment, but it can also be used in transactional/office settings and in software data flow. Whenever the product or material is moved, there is a risk of loss, damage, and increased processing time.
This is specifically referring to excess inventory, and there are often contractual requirements to carry a certain amount of buffer stock to ensure the customer limits the risk of running out of products. Inventory is a waste, as it ties up company capital that cannot be reinvested in growth. Inventory can include raw material, work in process (WIP), finished parts, and finished assemblies ready to ship. Common causes of excess inventory are poor forecasting, utilizing a push instead of a pull process, batch processing, and unbalanced production capabilities.
Motion is work done by the operator during production, but is done in excess of an ideal state. This can result from poor ergonomics or process flow with equipment and needing supplies not co-located. A few great tools to mediate this waste are a spaghetti diagram and utilizing “point-of-use” tooling wherever possible.
Over processing is non-value added work added to a product or process that is not needed. As defined previously, value is defined as what the customer is willing to pay for. Think about the minimum viable requirements the customer is seeking and/or meets the function the product is intended to perform; anything beyond this is waste. Don’t confuse this waste with luxury type goods, in this case, the over processing becomes a feature the customer is willing to pay for (This can be a balancing act).
This is widely described as the worst waste as it encompasses all the other wastes. Over production will generate and potentially hide all other wastes and is often found in improper forecasting techniques, under-utilization of process data to make timely decisions, batch processing, creating process bottlenecks, and producing at a rate higher than demanded.
Employees will often have skills and talents outside the realm of the job they were hire to do. It is a waste for an organization to not utilize these employees to their full potential. Often times, this waste will manifest itself through problems and challenges only being solved by subject matter experts, a toxic corporate culture not diverse or inclusive where all employees feel their ideas and improvements are valued, and not creating a system to attract new innovations.
How to Identify Waste in a Process?
A phrase in lean, “Go to the Gemba”, meaning go to where the action is happening. There is only so much knowledge to be gained by drawing a process map based on experience and opinions of subject matter experts. The most effective method to gather process intelligence is to go to where the action is happening and monitor. Take care to minimize talking and process interference to disturb the natural flow – kind of like watching animals in the wild, try not to disturb them or make your presence known. A great technique, if allowable, is to secretly place a camera to monitor the process. This will provide minimal interruption to the production process and give the investigating team the ability to review the footage many times.
The key deliverable when monitoring a process is to determine the steps of the process, assign clear start and stop points for each task, and identify any waste or improvement ideas that crop up during the investigation. It is useful to have multiple people independently log the process steps and compare notes at the end (Don’t utilize any pre-written procedures to determine these steps). Time this audit many times to produce a large dataset of the process time for each step – this will reduce potential bias associated with a single observation.
After reviewing the footage, involve the operators and employees responsible for the process by asking for their ideas and brainstorm to develop any ideas previously generated.
A way to remember the 8 wastes is “TIM WOODS” – Transportation, Inventory, Motion, Waiting, Over Production, Over Processing, Defects, Skills(People).