This is a primer intended to give an overview and an introduction about the lean production, partly based on a small e-book: Lean Primer by Craig Larman and Bas Vodde.
Lean thinking is a large system originally started by Toyota for product and project development and then spanning to service, sales, HR and so on.
The first page sets the tone: take a relay race, where runners have to wait for the baton from their running colleague. Such a waste and under-utilization.
Traditional management would try to “optimize the resource utilization”, maybe asking them to run more races in parallel.
In contrast, the central idea in lean thinking is:
watch the baton, not the runners.
Several tools (like the Kanban) have been popularized by Toyota but they are not the pillars of the lean system.
Rather the power behind is a company’s management commitment to continuously invest in its people and promote a culture of continuous improvement.
Toyota’s real advantage was its ability to harness the intellect of ‘ordinary’ employees.
The lean goals (as depicted in the house roof) are sustainable shortest lead time, best quality and value (to people and society), most customer delight, lowest cost, high morale, safety.
Broadly, the global or system goal of lean thinking is to quickly deliver things of value (to the customer and society) in shorter and shorter cycle times of all processes, without reducing quality, or at an unsustainable or unsafe pace.
It’s a long-term philosophy and everyone is expected to act following the lean principles. The managers act as teachers of thinking skills. They learn and live the principles and coach their teams.
A matrix of management cultures is presented; the ideal lean managers/teachers are in the top-left quadrant.
|expert knowledge of the work||only general management knowledge|
|bottom-up||coach/mentor; builder of a learning organization||facilitator|
|top-down||detailed task master||bureaucrat|
Pillars of lean
The two pillars of the Toyota system were continuous improvement (often called as in original, kaizen) and respect for the people.
Each of them is based on several ideas and tools, you can see them in the picture above. But note that they are just tools.
Reducing lean thinking to kanban, queue management and other tools is like reducing
a working democracy to voting.
Consequently, Lean Six Sigma (a compilation of tools and training focused on isolated projects to drive down unit cost) is viewed by Toyota people to represent Six Sigma tools but not to represent real lean thinking.
The book is not going into details about the single tools but a wide literature exists about them and several of them have been incorporated into software processes, as lean software management and kanban (I will come back to them in future posts).
Respect for people
Don’t trouble your customer
- your customer is anyone who consumes your work or decisions
- relentlessly analyze and change to stop troubling them
- don’t force people to do wasteful work
- don’t give them defects
- don’t make them wait
- don’t impose wishful thinking on them
- don’t overload them
Develop People and Then Build Products
- managers act as teachers, not directors
- mentor people closely, for years, in engineering and problem solving
- teach people to analyze root causes and make problems visible; then they discover how to improve
Managers “Walk the Talk”
Managers understand and act on the goal of eliminating waste and “continuous improvement” in their own actions and decisions—and employees see this.
- real, jelled teams of 5-6 people
- team-work, not group-work, culture
- form long relationships based on trust
- help partners improve and stay profitable
Teams & Individuals Evolve Their Own Practices & Improvements
- management challenges people to change and may ask what to improve , but…
- workers learn problem solving and reflection skills and then…
- decide how to improve
Go see for yourself
This fundamental lean principle means that all people and especially the managers should not stay in their offices and rely only on information via reports and status meetings but should frequently go the place of real work and understand for themselves, including talking directly with the customers.
It’s similar to the Management by walking around principle made famous by HP.
Improve for improvements’ sake and repeat it forever.
- spread knowledge: share rather than enforce practices.
- small, incremental, relentless change of anything. Challenge everything.
- 5 Whys. In response to a problem, asks yourself why? at least 5 times. Stop and fix when there is a problem.
- eyes for waste. reduce everything that is waste (variability, overproduction, waiting or delay, handoff, Work in Progress, information and knowledge scatter, multitasking, defects, wishful thinking, …)
Even when you are making good money and you have established processes, there is still room for changes.
Work toward flow
(lower batch size, Q size, cycle time)
Together with the two pillars, a set of lean principles form the overall system of lean and it’s emphasized that you should implement lean as a global system, with all the elements together, instead of cherry-picking some tools or principles.
- Base management decisions on a long-term philosophy, even at the expense of short-term financial goals.
- Move toward flow; move to ever-smaller batch sizes and cycle times to deliver value to the customer fast and expose weakness.
- Use pull systems instead of push; decide as late as possible. In this way you have the most information to make an informed decision and do not waste resources.
- Level the work—reduce variability and overburden to remove unevenness. Identify bottlenecks, take less work in cycle, de-scope, spread the work and skill-cross train.
- Build a culture of stopping and fixing problems; teach everyone to methodically study problems. Not only fix, but apply 5 Whys analysis to understand the root causes, and really fix it.
- Master norms (practices) to enable kaizen and employee empowerment. These are changeable working agreements, not rigid organization standards.
- Use simple visual management to reveal problems and coordinate. For example a big board with cards hanged on the wall.
- Use only well-tested technology that serves your people and process.
- Grow leaders from within who thoroughly understand the work, live the philosophy, and teach it to others. Leaders from within may not be a good idea if your existing culture is not lean—the point is educated lean-thinking leaders.
- Develop exceptional people and teams who follow your company’s philosophy. This reflects the Toyota “build (lean thinking) people, then products” message; it includes “towering technical competence”
- Respect your extended network of partners by challenging them to grow and helping them improve. Bring partners into lean thinking as well; there is an emphasis on sharing knowledge and openness.
- Go see for yourself at the real place of work to really understand the situation and help.
- Make decisions slowly by consensus, thoroughly considering options; implement rapidly. Activities such as kaizen events (retrospectives) support this.
- Become and sustain a learning organization through relentless reflection and kaizen.
To conclude, here is a metaphor shared in lean education: lake and rocks.
The depth of the water may represent the inventory level, batch size, or cycle time. When the water is high (large batch or inventory size, or long cycle time), many rocks are hidden. These rocks represent weaknesses.
Decreasing the water, for example through shorter release cycles, makes the ineffective practices (“the rocks”) become painfully obvious and a force for improvements.