The 7 Wastes of Lean (2024)

Understanding the concept of “waste” and the eight wastes of lean begins with distinguishing a difference between what creates “value” and what is unnecessary waste.

Value, or a “value-adding activity” is anything thattransformsmaterial into something the customer actually wants and is willing to pay for.

For example, a customer will gladly pay for a stamping press to form a metal part, or a carpenter to cut wood to size.

But a customer does not want to pay for walking to pick up a tool or part, or delays caused by waiting on a fork truck or a broken machine. These wasteful examples generate no value!

So a value-adding activitytransformsmaterial into something closer to what the customer wants. A wasteful activity (or “non-value-adding activity”) does not. No transformation takes place!

See how this time lapse video highlights waste and value in an assembly operation.

While focusing on eliminating waste is important and also popular in lean circles, eliminating the 7 wastes of lean is actually only one part of the picture!

The more complete picture paints the problemof threeevils that must be dealt with to handle resources efficiently and effectively.

Three Japanese words describe these evils:

1. Mudarepresents wastefulness and is where we get the 7 wastes of lean. Muda occurs whenever resources are consumed without creating value for the customer.
2. Murarepresents unevenness and has to do with variation within the production system. Wherever you witness a buildup of inventory (e.g. overproduction) you are seeingmura.It is present whenever a schedule fluctuates or when an individual operator is made to “hurry up and wait” when working a job.
3. Murirepresents over burden. It will strain machines and people and work them excessively.

Originally, there were seven categories of waste, defined below.

Toyota identified seven original wastes in the 1900s. It wasn’t until later that westerners added an 8th waste.

The 8th waste goes by various names. Some call it “skills” and add it onto the popular acronym TIMWOODS. Others call it “non-utilized talent,” or “creativity,” or even “genius.”

Regardless of the name, the meaning is the same: the failure to fully use and develop people’s capabilities.

While the 8th waste was not formally taught during the original development of the Toyota Production System, it is clear that a value for people and for developing their full potential was present from the beginning.

There is a fascinating quote from one of Toyota’s founders Eiji Toyoda.

“Employees are offering a very important part of their life to us. If we don’t use their time effectively, we are wasting their lives.”

Eiji Toyoda

Consequentially, we regard the 8th waste of Lean as the greatest waste of all! Because what greater waste is there than the waste of life itself?

Sometimes it is difficult to connect the eight wastes with tangible strategic goals.

For example, setting out to just “eliminate waste” may sound like a good idea, but the goal can quickly become vague and poorly defined.

Instead, we recommend considering these more-tangible goals below, first detailed by Masaaki Imai inGemba Kaizen, and taught in our course Kaizen Best Practices.

1. Improve Quality
2. Improve productivity
3. Reduce inventory
4. Shorten the production line
5. Reduce downtime
6. Reduce space
7. Reduce lead time

Any of the kaizen goals above will require waste elimination. They will also improve the financial performance of your organization.

So the next time you’re stumpedapplyingyour knowledge of the eight wastes of lean, consider making use of these kaizen strategies.

Various training methods can be used to teach the eight wastes on the job and are listed below.

While any of these training activities can be performed without an external curriculum, we highly recommend the use of video training to make initial and on-going training easy, time-efficient, and consistent across multiple shifts and trainers.

Create or use a simple scavenger hunt worksheet like this one and give employees time to observe processes and write down observations of each of the wastes. This is done best with the involvement of a coach who will periodically step in to review the observations and skillfully help the employee to see more.

Taiichi Ohno–a founder of the Toyota Production System–had a practice of placing new initiates in a circle drawn on the floor to teach them the seven wastes. He would instruct them to “stand in the circle” for hours and observe intently for problems and opportunities for improvement.

After a while, he would follow up on the learner and ask, “What did you see?” If they didn’t have a long list of observations, they were forced to stand in the circle longer.

While you don’t have to imitate Ohno’s method precisely, you may want to have associates similarly practice identifying wastes in the circle.

Another effective way to teach lean—especially in groups—is to record a process on video and then play it back for everyone to review and identify wastes and problems.

If you have a daily standup meeting, you can easily reinforce training by asking the facilitator to bring one or more examples of a waste that he or she has observed on the job.