LearnSixSigm
In this Article
In this article you will learn…
- The origins of Lean.
- How Lean is used.
- The five stages of a Lean project.
- How Lean works with Six Sigma.
Origins: The Toyota Production System
There's an easy answer to the question "What is Lean?" — It’s the Toyota Production System or TPS.
But what's that? It's a continuous improvement strategy developed by Toyota in the 1950s and 1960s. Taiichi Ohno and other managers at Toyota were intent on restructuring post the Second World War. They were likely heavily influenced by Henry Ford but developed their own culture and strategy around their philosophy of coaching and teaching the skills of teamwork and process improvement.
Did Lean Work for Toyota?
The next question might be — "Is it any good or would it work for my business?". I can only point to the success of Toyota in the period since. I worked for Ford briefly in the 1970s. They believed at that time their position was secure and the market held them in high regard.
The opinion of Toyota in the market by comparison was relatively lowly, expressed as — cheap and cheerful and probably OK for a while but likely to rust or fall apart in a few years. So where are Toyota now? They're the biggest selling brand worldwide. Even in the U.S. market alone they are very close to parity with Ford. What could that possibly be due to other than "The Pursuit of Perfection" (another Toyota watchword)
They were playing the long game, continuously striving to achieve better products at lower cost and delivering them faster to their customers. They were achieving that by actively coaching all of their employees right from the shop floor in problem solving and process improvement.
What is Lean and How is it Used?
The language and tools of Lean are those used in flow processes and so fit well when improvement in cycle time or delivery is key.
This means eliminating waste and improving flow getting things to the right places in the right quantities at the right time, while also being flexible to change.
Although Lean originated in high volume repetitive manufacturing it has been successfully employed in all kinds of manufacturing sectors and also in business process in call centres and healthcare.
It is often said that Lean is the "need for speed" where Six Sigma is instead the "need for quality" because of its focus on variation, specification and capability. However, we should never lose sight of the customer perspective — the Voice of the Customer — and the goal of producing better or faster or cheaper products and services. Never focus on delivering a cycle time gain or response improvement at the expense of quality or cost.
The Stages of a Lean Project
Lean projects follow a similar staged strategy or project plan to Six Sigma. The names for each step were likely translated from the original Japanese but they have standardised in English as follows:
- Define value for the customer
- Map the value stream
- Make the process flow
- Shift to pull
- Strive for perfection
The wording fits the assumption that there is a flow process at the heart. That might be a flow of material or assemblies, or products or information, or customers, or patients.
1. Define Value For The Customer
This makes us see our product or service from the customer viewpoint. What is it that the customer wants and is willing to pay for? With that as our yardstick what other things or actions are we doing that are of no value to the customer? These are traditionally excesses of: Transport, Inventory, Movement, Waiting, Overproduction, Overprocessing, Defects, and last but not least, Wasted human potential or skills.
2. Map the Value Stream
We review the current state of process and identify how material or information flows through it. This forms the foundation for our process improvement. It shows inventory and cycle times and directs us to where gains may be made.
3. Make the Process Flow
Eliminate non value add, increase the speed of throughput, reduce the cycle time for the customer. A key indicator of flow is inventory. Excess inventory is an indicator of bottlenecks in the process. Eliminating flow-holds and reducing inventory drives cycle time improvement for the customer.
4. Shift to Pull
We make the process respond only to customer demand. Ideally produce what the customer wants when he or she wants it. The classic trigger is a space on the shelf. When the customer buys one it leaves a space which is the signal to make another. The same space migrates down the production line triggering replenishment without any command or control mechanism just simple visual signals.
5. Strive for Perfection
We lock in the improvements to make sure they stay fixed. Train the team, communicate with stakeholders, document the new process. Celebrate and reward the success and start the process over on the next level improvement goal.
What about Lean Six Sigma?
In the last few years we have seen the emergence of Lean Six Sigma, which is a union of both the Six Sigma strategy from Motorola and the Lean or Toyota Production System. It recognizes that there isn’t one size that fits all but gives you permission to use the best tool for the job. For me you can have the best of both worlds and span projects in high volume repetitive manufacturing, transactional or specialist business processes and cutting edge technical equipment. At least until something better comes along.
Related:
