Push Scheduling Has Its Place
The Toyota Way is not preoccupied with adhering to Principle 3, Use “pull” systems to avoid overproduction. There are many examples of push scheduling throughout Toyota. One example is when dealing with parts shipped from Japan to the United States or even moved across the United States. They use traditional scheduling systems to order these parts, with the appropriate lead time to get them to the plant as scheduled. Also the engineering of new products is a tightly scheduled operation, as I have described in The Prius Blueprint.
When Toyota managers do schedule, they are preoccupied with timeliness. In other words, the schedule is not simply a guideline that you should do your best to make, more or less. It is a deadline and you move heaven and earth to make the deadline. So, even in scheduled systems, materials and information move remarkably smoothly. Scheduled systems work best when lead times are very short; for example, ordering parts every day instead of ordering parts once a month. So, when it comes to scheduling, Toyota works to make lead times as short as possible.
These days Toyota is increasingly using computer systems for scheduling. For example, when ordering parts from suppliers, Toyota is moving to electronic kanban rather than sorting and sending cards back. In this case, it does not have to be either/or. As we will see in Use Visual Control So No Problems Are Hidden on visual control, Toyota will often use a computer system for scheduling some operations, but then use manual cues like cards or white boards to visually control the process. For example, the logistics planning backbone of Toyota’s Service Parts Distribution Centers is a computerized scheduling system but “process control” whiteboards actually control the operations.
If you are using the Toyota Way to become lean, the lesson here is that you don’t have to get hung up imitating Toyota’s use of specific tools so you can appear to be lean like Toyota. The Toyota Way is a philosophy and a set of tools that must be appropriately applied to your situation. But understand that these principles are something to believe in and strive for. They are part of a greater system that is seeking harmony and perfection to sustain success. As you move on through the chapters in this Section II of the Toyota Way, “The Right Process Will Produce the Right Results,” you’ll continue to see how each of these processes is dependent on the others