What is lean? I would like to answer that question with an explanation based on the description given by the inventor of lean, Taiichi Ohno.
Pull and push
Hopp and Spearman define pull in their work Factory Physics based on Little’s law. It’s a good definition that states that pull sets limits on any current workload while push doesn’t. However, there’s more to lean than pull.
What is Lean?
The inventor of the concept of lean is Taiichi Ohno. Ohno has written two books in which he summarizes the results of decades of experiments. These experiments and results are both comprehensive and have been tested by others. Ohno condenses the results into two principles: Just-In-Time (JIT) and jidoka (autonomation). Just-In-Time is the result that Ohno would like to achieve and the solution is Kanban (visual management). Kanban makes it possible for different actors to work together without the intervention of management or other planners. Besides these principles, Ohno also discusses 5S and wastefulness; however, his main focus is the challenge of getting people to work together.
Lean is Self-Organization
People who interact without the interference of outside actors practice self-organization. The term was defined in complexity research and is based on Claude Shannon’s information theory. When a number of actors, such as the participants of a group, have more interactions (more organization), the probability collaborating behavior (value-creating work) increases. This is called self-organization. An important prerequisite for self-organization is that the interactions are initiated by the actors themselves. There can’t be any outside actors (bosses, project leaders, etc.) that hinder or block interaction. However, the group does need information and feedback in order to deal with events appropriately.
Within a company, individuals will be a part of a greater whole (an infrastructure) that sets prerequisites for the groups to function well. In production, the production facility is this infrastructure. Within strategy and development we build an infrastructure through a network of Pulse boards and Pulse meetings.
Lean is Networks
With self-organization, the group has an opportunity to act more coordinated. Work that has previously been waiting for the contribution of another actor can now be done. However, with increased action there are also more problems that need to be solved in order for work to progress. The probability of problems appearing increases the greater organized the organization is. Therefore there is both a positive and a negative side. We can turn this into an equation:
Self-organizing (the ability to do things) = the degree of organization - problems that appear
With the help of visual management (such as Kanban, Pulse or Scum), increased organization is made possible. With the help of Jidoka (“pull the string” and other “take-care-of-problems-now methods”) you learn to deal with the problems that come up. When the “ability to do things” increases it’s a measure of increased productivity and quality. Productivity and quality improvements emerge from the interactions that come from self-organization. In theory, lean is therefore a concept that makes self-organization possible.
From Large-Scale to Networks
The time before lean was dominated by large-scale thinking. Nowadays we think in terms of networks. This has changed the duties of management. Previously, management lead and distributed work while in today’s world they build networks.
Read a blog entry about lean in action here.