The VSM Sham - Why It Doesn't Work

The VSM is a snapshot. The information gathered this month will likely be different from the information in 3 months. Moving target. However, I do believe some of the information is interesting. I guess it could be used as a record of the "before condition", prior to implementation of a pull system? Or, I suppose it could be a persuasive way to illustrate the dysfunction of a current push system? A little shock value possibly? Again, interesting information but...it's not necessary for action. Any manufacturer operating in a push system suffers from all the problems associated with it. Mapped or not, all issues are present.

This mapping focuses attention on the symptoms associated with push systems. The lack of synchronization and pace in push systems results in the symptoms illustrated in a VSM. The use of the VSM, current and future state maps, to target areas for improvement is where failures occur. Generally, an attempt is made to "lean out" an area identified from the VSM. Tools/concepts/methods are applied. Kanban, standard work, visual management, 5S, etc.

Here's the problem. These tools/concepts/methods were developed over time in a pull system. Ohno said, "Each idea was conceived and developed in response to a need." These "needs" were the needs of a pull system. Yet, they're regularly implemented in the middle of push systems. Is it any wonder that failure occurs? No, it's absolutely assured! But, instead of understanding that these tools/methods/concepts don't work in push systems, blame is placed elsewhere.

After 1962, Toyota was working on expansion of their kanban system to their suppliers. They were invited to Toyota to see it and study it up close. Ohno said, "This way of teaching gave us the ability to demonstrate an efficient production method in an actual production plant. As a matter of fact, they would have had difficulty understanding the system without seeing it in action."

This "difficulty understanding the system without seeing it in action" is the source of many failures because tools/concepts/methods meant for pull systems are thrown into push systems where they don't work.