A basic introduction to lean requires making a distinction between activities that are “value-added” (VA) and other activities that are “non-value-added” (NVA). These non-value-added activities are pure waste!
Eliminating this waste is at the heart of lean.
Traditionally, there are 7 types of waste, which are explained in this article.
Defining Value and Waste
Value can be defined as anything the customer wants. The activities that create this value are called “value-added” activities. These are activities that transform material into something the customer desires–activities like: cutting, gluing, assembling, stamping, bending, packaging, etc.
Anything else is an activity that is non-value-added and waste. It does not transform material into what the customer wants.
The 7 Wastes of Lean
Each of the 7 wastes of lean are defined and summarized below.
The Waste of Transportation
Transportation of all kinds is wasteful, including the use of: forklifts, dollies, conveyors, trucks, and even walking inventory from one place to another.
However, much can be accomplished by relocating processes, creating a better floor plan, reducing batch sizes, and creating areas of continuous flow.
The Waste of Inventory
Inventory of all kinds is waste! It locks up cash, deteriorates over time, takes up space, increases overhead, and hides quality problems.
It’s a symptom of bottlenecks, inefficiencies, and poor process flow. The moment the flow is interrupted between two processes, the inventory starts to pile up.
Therefore, inventory is not desirable!
But as you solve problems and practice kaizen (aka continuous improvement) you can eliminate a ton of inventory.
The Waste of Motion
Human motion may be necessary to perform your work, but motion by itself does not create value!
An operator might even move fast, work hard, and break a sweat, but all the motion involved is actually wasteful.
We don’t want operators to have to move fast—or to bend, reach, lift, or walk. We want to eliminate wasteful motion in the first place so that their work is efficient, smooth, easy, and struggle-free.
The Waste of Over Processing
Over processing can be understood in two ways.
- Whenever you have a defect and have to correct it, this is over processing. Some people call it the “waste of correction.”
- Over processing is also whenever you spend more effort, time, or resources into something than necessary.
The waste of over processing is commonly found around processes like: sanding, painting, welding, grinding, heating, washing, cleaning, etc.
Without a clear standard and effective training, lots of extra processing can creep in. It’s not even required by your customer, but you’re paying for it anyway!
The Waste of Over Production
Over production is regarded as the worst of all of the 7 wastes because it multiplies all the other wastes.
Batching is a prime example of over production, but it is not the only one!
Whenever you create something sooner than it is immediately needed, you over produce.
In practice, whenever you see inventory sitting around (and not being actively used), you’re witnessing the downstream effects of over production.
The Waste of Defects
Defects are a clear and obvious waste: a customer will never be willing to pay for them!
So defects of all kinds must be eliminated and the highest level of quality must be pursued.
What’s the 8th Waste of Lean?
The original wastes identified by Taiichi Ohno at Toyota in the 1900s were seven. Later on, others suggested that an 8th waste should be added for unrealized human potential.
This waste goes by many names: non-utilized talent, skills, creativity, genius, and more. They all describe the same thing: an under-engaged workforce.
Although this waste is less tangible than the original 7 wastes, we can readily agree that one of the greatest wastes of all is to waste someone’s time and creativity.
To be world-class organization, it’s not enough to employ someone’s hands. We must also employ their brain!
In many ways, this is what “respect for people” and lean is all about.
Other topics of discussion: