Muda

8 Wastes of Lean 

Waste, also known as Muda(無駄) in Japanese,  is anything other than the right amount of inputs, materials, processing, space or time needed that are important to add value to the product. This definition comes from the president of Toyota, a recognized worldwide leader in Lean. In any sequence of work, there is a number of task steps. What Toyota’s president, Mr. Cho, means is that this list of steps should be reduced down to the minimum, essential things that are required to provide a product or service. Everything else should be eliminated. Many people believe that every activity has some intrinsic value. In Lean, we’re going to take a much more rigorous approach.

We want to reduce the amount of work to things that are essential in providing value to the customer. There are three questions we ask when we define value.

• Is the customer willing to pay for the activity?
• Does the activity add value to the goods or service?
• Is the activity completed for the first time?

These three questions serve as a litmus test we use in Lean to determine if something is value-add. An activity or task step must answer “yes” to all three of these questions to be considered value added. Is the customer ready to pay for the activity? The most important thing to understand about value is that it’s determined from the customer’s perspective. It’s the voice of the customer we’re looking for here.

Generally speaking, customers are looking for the right product, at the right price, at the right time. There are a lot of things they’re not going to be willing to pay for. If you have damaged or incomplete products, or maybe even an internal inspection that’s required to ensure quality, customers won’t care. They only expect the right products at the right price at the right time.

There are three rules of waste. The first rule is that waste exists at all levels of the organization. It doesn’t matter what level or area of the business you look into; waste has invaded all areas. There’s no process that is exempt from waste. Only 3% to 5% of a process is typically considered value-added. The second rule is that waste must be identified and eliminated. The third rule is that all employees must be trained to recognize waste.

In the original Toyota Production System, there were only 7 types of wastes ( Muda), as identified by Taiichi Ohno, “father” of the TPS. It was later evolved and updated to include the eighth waste- unused human intellect, and hence there are currently 2 versions of wastes interpretation – 7 wastes or 8 wastes. In this article, we will be discussing the 8 wastes.

There are a few versions of acronyms that will help us to remember the 8 wastes, 2 of them are given below. There is no right or wrong, just choose any version to help you to remember the wastes better – you can even create your own version.

Version 1: TIM WOODS

• T – Transport
• I – Inventory
• M – Motion
• W – Waiting
• O – Overproduction
• O – Over-processing
• D – Defects
• S – unused Skills

Version 2: WORMPIIT

• W – Waiting
• O – Overproduction
• R – Rework
• M – Motion
• P -over-Processing
• I – Inventory
• I- unused Intellect
• T – Transportation

Below is a quick overview of the 8 wastes using the WORMPIIT acronym.

The first type of waste is waiting, like when you are waiting on parts or information, or when you are waiting on others to provide you things that you need for your process to work.

The second type of waste is over-production, or producing too much too soon. You may be working ahead of your deadlines or may have to do a lot of rework. Overproduction includes any type of reprocess or repair on something that has been done upstream in an earlier process.

The third type of waste is rework. This includes any process or product that has to be redone according to customer requirements.

Fourth is the waste of motion, which includes any motion of the worker that does not provide value. Sometimes people confuse activity for productivity, and that’s not the case. A lot of times motion is just wasteful motion. We look to eliminate that.

Fifth waste of processing is defined as over-processing or process variability when we perform steps that are not necessary.

The sixth waste is the waste of inventory. This is holding any more than the minimum inventory to get the job done. Seventh is the waste of intellect, and that is the failure to utilize the time and talents of your people.

The last waste is the waste of transportation.

The 8 types of waste will be interpreted and contextualized /customized  specifically for your company during our in-house Lean Thinking training.

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