The 3 Major Ways Used To Categorize Wastes By Influential Japanese Gurus
Norman Bodek often called “The Godfather of Lean” couldn’t imagine how simple the instructions of Mr. Ohno which were the basis of Toyota Production System. Norman said (1988): “There’s nothing very complex in the magic of Mr. Ohno’s teachings”, he continues: “In fact, it is often confusing listening to him because he talks so simply, often just saying to look for and eliminate waste. We cannot believe that it is that simple — but it is true.”
“ Simplicity is the ultimate sophistication .” Leonardo da Vinci
Learning to see wastes is the first skill that you have to develop with your people, and eliminating those wastes should be on the top of your priorities. Developing small wins of discovering wastes and converting them into value was the heart of Toyota Production System. From the beginning, where your customer places an order to the point when the customer receives what he asked for, there are many processes and activities in the way. Your customer is not willing to pay for you, because you just have the cutting edge technology, or the best experts in a certain field, customers only pay for what solves their problems regardless of what you do to come up with that product or this service. The only one who cares about your product/service is You!
“All we are doing is looking at the time line, from the moment the customer gives us an order to the point when we collect the cash. And we are reducing that time line by removing the non-value-added wastes.” Taiichi Ohno
Source: ASQ Quality Press, 2012
So, understanding wastes and how to identify them across your value chain is the lifeblood for your lean implementation. Knowing the types and classifications of wastes will help you to easily discover them. There’re many classifications of wastes, but in this article, I’m going to share with you the major three:
- Taiichi Ohno’s classification (7 wastes)
- Yasuhiro Monden’s classification (4 wastes)
- Hiroyuki Hirano’s classification (5MQS wastes)
Taiichi Ohno’s Classification
In my last article, I have briefly discussed the seven wastes which have been introduced by Taiichi Ohno (1988) — one of the inventors of Toyota legendary. It’s very important how you prelude these types of wastes to your people, instead of just informing them with the seven wastes in a bullet format or using this acronym ‘TIMWOOD” — it’s only a good way for remembering, but not for learning. You can open a discussion with your people using questions.
The Socratic Method to Unlock People’s Capability
A lean leader should realize the incredible power of questions and how it could shape people’s thoughts and let them learn virtually anything. In fact the entire Socratic Method is based on the teacher is doing nothing but asking questions, directing the student’s focus and getting them to come up with their own answers.
“He who asks questions cannot avoid the answers” Cameron Proverb
- Are we producing too much or too soon?
- Are operators waiting for parts to arrive or for a machine to finish a cycle?
- Are we keeping conveyance to a minimum?
- Are we over-processing parts?
- Do we keep on the workstation more parts and components than the minimum to get the job done?
- Do we keep motion that does not contribute directly to value-added to a minimum?
- Do we avoid the need for rework or repairs?
Many “lean consultant” has started a training session by writing the 7 wastes on a board, and never returned to them again because they were too busy with the tools! Using the Socratic Style in your training will make a big difference with your people and how they perceive the seven wastes, following the above questions with the WHYquestion will make you discover the real root causes to these wastes and then you’re about to drive them all out.
Yasuhiro Monden’s Classification
“Toyota Production System: An integrated approach to just in time” is one the best books that describes TPS from an academic standpoint. Monden introduced four kinds of wastes that can be found in manufacturing operations:
- Excessive production resources
- Excessive inventory
- Unnecessary capital investment
Excessive production resources could take many shapes; excessive workforce, excessive facilities, excessive inventory, when these elements exist in a amounts more than necessary, whether they are people, equipment, materials or products, they only increase cash outlay (costs) and add no value.
Excessive production resources create the secondary waste — overproduction. Overproduction is regarded as the worst type of waste at TOYOTA. Over production is to continue working when essential operations should be stopped.
Overproduction causes the third type of waste — excessive inventories. Extra inventory creates the need for more manpower, equipment, and floor space to transport and stock the inventory. These extra jobs will further make overproduction invisible.
Given the existence of excessive resources, overproduction and inventory over time, demand for the fourth type of waste would develop. This fourth type, unnecessary capital investment, includes the following:
- Building a warehouse to store extra inventory
- Hiring extra workers to transport the inventory to the new warehouse
- Purchasing a forklift for each transporter
- Hiring an inventory control clerk to work in the new warehouse
- Hiring an operator to repair damaged inventory
- Establishing processes to manage conditions and quantities of different types of inventory
- Hiring a person to do computerized inventory control
These four sources of wastes raise administrative cost, direct material costs and direct or indirect labor costs and overhead costs such as depreciation, etc.
Hiroyuki Hirano’s classification
Stability is a key element in sustaining the success of Toyota. Sustaining stability in the 5Ms; Man, Machine, Method, Material and Management is the first goal that a lean leader has to focus on, but it would be a little bit harder to reach stability, when the 5Ms are fatty. By maintaining stable 5Ms and freeing them from wastes, you can accomplish your highest targets of Quality and Safety.
Source: Hirano, 1990
The 5MQS scheme identifies seven types of waste, five of which begin with the letter “M”: Man, Material, Machine, Method, and Management. The “Q” in the 5MQS formula stands for Quality and the “S” for Safety.
This figure shows the seven categories of wastes and how they include many hidden opportunities for improvement if we just stop and take a look. Although the first classification for wastes by Ohno is the most famous one, the other two are very valuable and could be used. In my perspective, Monden’s classification is a re-formulation of what Ohno stated (The 7 wastes) and it gives us an understanding of what the root cause of overproduction — excessive production resources. On the other hand, Hirano’s framework is a good one for organizations that start their lean implementation, as it directly hits the five foundations (5Ms) for any organization looking for stability, quality and safer workplace.
Begin with the end in mind
All things are created twice, so having a framework for identifying wastes in mind is a good way to keep your people motivated to waste elimination. Although, it is not a necessity that they’re going to discover wastes just by knowing that, but visualizing the end target in mind and keep moving toward it is better than getting to hunt wastes in a chaotic manner. After that, you can start your Waste Walk individually or with cross-functional team to identify Muda at your workplace.
Last but not least, eliminate waste purposefully, get the most out of the Waste Walk, and let your team experience the power of lean by unlocking the hidden opportunities for improvement.
If you’d like to read more like this article you can visit:
- 10 Simple Questions to Assess Your Organization’s Readiness to Improvement Programs
- The No.1 Skill You Need to Have to Master Your Lean Learning Journey and don’t leave before getting your copy of “The Waste Hunting Worksheet: 5 steps to hunt wastes at any workplace with a blank mind.”