Wednesday, September 18, 2013
The Risk of the Lean Production
Lean Production, which originates from the Toyota Production System (TPS), took the manufacture industry to a brand new step. The industry evolved from the age of the craftsman through the methods of mass production, and into an era that combined the machine and human after the introduction of the Lean Production. 
The Lean Production overcomes several drawback of a Mass Production. Mass Production succeed in significantly increasing the productivity and reducing the cost by producing lots of standardized product. It relies on a high volume of production, and it's hard for the products produced via Mass Production to expand its variety. The Lean Production combine the flexibility and quality of human workers and the efficiency and low cost of the machine.
Even though a lot of companies, especially Japanese companies, has successfully implement the lean production, saving or boosting their business, there are also lots of firms who failed to do so. The failure to implement the lean production could be either from the inaccurate understanding of the manager who decide the implement it, or even from its inherent disadvantage.
Philosophy, Rather than the Tools, Matter
One of the most common mistakes is that the companies only see the tools Toyota uses and ignore the philosophy behind the lean production.  The companies may purchases devices like andon signal, heijunka board, kanban or employee glass wall, and try to copy the success of the Toyota. They ignores the fact that it's the philosophy of lean production that matter and these devices are nothing but the tools to help achieve the philosophy.
The philosophy is to study the process and to eliminate the waste (part of the process that doesn't create value). It means that the leader should authorize and encourage their worker to think more about their work and make recommendations. Some companies who simply adopt those tools but don't change their manager style definitely won't benefit from the lean production.
Lean Production has higher requirement for the workers than the Mass Production. A worker from Ford usually doesn't know how to fit a car because he/she only repeat a simple behavior day after day. On the contrary, many Toyota workers can do it. Each of Toyota workers are usually responsible for a certain module of the car, like the engine or brake, instead of simply turning a screw.
The problem comes from the higher expectation. Not all the workers are high self-motivated, looking for more responsibilities to fulfill their value. The incentive system should be adjusted to align with the higher requirement. Under the lean production, the experience of the seniors workers become more valuable, so the incentive system should be designed to keep those experience workers.
Trade-off for Using Common Modular
Compared with the Mass Production, the advantage of the Lean Production is that it could handle more variety of the products. However, the variety brings more complexity, which means the extra cost. In order the offset the increased expenditure, the Lean Production tend to use common parts and designs across different products, and it's pretty common in the automobile industry.
However, the methods bring more risk to the companies. It becomes a more serious problem when the technologies become much more complicated and defects are hard to identify because they get spread out. It means that if the company purchase flawed components from its supplier and they are used across many products, all of these products will fail.
There are more reasons that can account for the failure of the lean production, like not having a performance metric aligned with it, or implementing it without working the suppliers and customers. What else reasons could you think of?
Another question is that we have emphasized that the Lean Production should be implemented as a whole system. We shouldn't just simply copy the devices used by Toyota. Then, how should we start? How we could implement with less organizational resistance?