in route. This may lead to another waste: waiting. One of the causes of this type of waste may be poor workplace layout.
The next waste is inventory. This waste describes an excess of things, whether it is parts, supplies, equipment, paperwork, or data. Accumulating and storing inventory costs money, so a major effect of this waste is reduced cash flow. We may lose production because we are looking for things in our disorganized storage areas, and inventory may get damaged or become obsolete before we can use it. We know we have excess inventory if there are stockpiles of materials or messy storage areas. The root cause of this type of waste is a just‐in‐case mentality, which might also be driven by an unreliable supply chain.
Next is the waste of motion, which is the movement of people, in contrast to transportation, which is the movement of things. Often these two wastes occur together, since it is likely that people are moving the materials around. Motion waste could stem from a poorly designed process, where operators must use excessive motion to get their jobs done. Motion waste may result in worker injury.
Waiting waste occurs when people wait for other people. This waste is incurred when meetings start late, when people must wait for information before they can move on to the next step, and when people wait for products or machines to be available. We can also think of this waste another way, in which information, products, or machines are waiting for the people to act upon them. Waiting increases cycle times and may increase overtime hours. It can be due to unbalanced workloads or a push environment, where products are sent downstream even if the next process is not ready for them.
Next we have overproduction waste. A direct consequence of overproducing is inventory waste. It can also trigger waiting waste for work‐in‐process parts.
Over‐processing waste is doing more than the customer is willing to pay for. This waste includes performing inspections. The customer is not willing to pay more for inspection; they expect the product to be made right in the first place. Over‐processing waste could also be incurred by adding features to a product or service that are not valued by the customer. This type of waste may result in longer lead times for delivery and a frustrated workforce that is asked to do tasks that are not adding value.
Of course, a major contributor to waste is defects. When we have defects, we increase internal and external failure costs and create dissatisfied customers.
The final waste is the waste of skills. This is the waste of an organization not using employees’ aptitudes to their fullest extent. This waste can result in frustrated workers, absenteeism, and turnover.
There are many interconnections among the various forms of waste. When there is transportation waste, chances are there is also motion waste. If these two wastes exist, there might also be waiting waste. Overproduction leads to inventory waste, and so on. Many of the root causes of these wastes also overlap. For example, lack of training is a root cause for transportation, motion, waiting, defects, and skills wastes. Root causes for each of the wastes are summarized in Table 2.2.
2.4.2.2 Visual Management
A major tenet of Lean is visual management, a technique that makes the current status of inputs, outputs, or the process readily apparent at a glance. In general, visual‐management techniques are inexpensive, simple, unambiguous, and immediate. By using visual management, problems are easily detected and so can be corrected quickly.
Visual management tools are often low‐tech, such as using colored tape on the factory floor to show where inventory belongs, where someone shouldn’t stand, or where fork trucks will be traveling. Racks and bins can be color‐coded by part type. Indicator lights on machines can be used to signal run status, and pictographs of work instructions allow operators to easily reference process steps. Maintenance charts can show the latest service performed, and statistical process‐control charts show the current process performance. Visual management can certainly be used in a manufacturing plant, but it also can be used in an office, hospital, restaurant, or any type of workplace.
Table 2.2 Root causes of the Eight Wastes.
| Waste | Root Cause |
|---|---|
| Transportation | Poor layout Lack of cross‐training |
| Inventory | Just‐in‐case mentality Unreliable supply chain |
| Motion | Poor layout Lack of cross‐training Insufficient equipment |
| Waiting | Too many handoffs Push environment Unbalanced workloads Lack of cross‐training |
| Overproduction | Lack of systems thinking Push environment Individuals valued over teams |
| Over‐processing | Lack of trust Unclear customer requirements |
| Defects | Poor training Non‐standard work Lack of job aids Poor communication |
| Skills | Lack of trust Lack of training Silo thinking |
2.4.2.3 The 5S Method
The tool known as 5S is defined as a physical methodology that leads to a workplace that is clean, uncluttered, safe, and well organized, resulting in reduced waste and increased productivity. The tool helps create a quality work environment, both physical and mentally.
The 5S philosophy applies in any work area suited for visual control and Lean production. 5S is derived from the following Japanese terms that refer to creating such a workplace:
Seiri: To separate needed tools, parts, and instructions from unneeded material and to remove the unneeded ones.
Seiton: To neatly arrange and identify parts and tools for ease of use.
Seiso: To conduct a cleanup campaign.
Seiketsu: To conduct seiri, seiton, and seiso daily to maintain a workplace in perfect condition.
Shitsuke: To form the habit of always following the first four S’s.
Table 2.3 lists the Japanese terms and the English translations of the 5S methods.
Benefits to be derived from implementing a 5S program include:
Improved safety
Higher equipment availability
Lower defect rates
Reduced costs
Increase production agility and flexibilityTable 2.3 The 5S methods.JapaneseTranslatedEnglishDefinitionSeiriOrganizeSortEliminate whatever is not needed by separating needed tools, parts, and instructions from unneeded material.SeitonOrderlinessSet in orderOrganize whatever remains
