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Chapter 7. Leveling: Be More Like the Tortoise Than the Hare 157

customer, but a defined agreement that represents the needs of the customer
that have been smoothed for the benefit of your processes.
Since this is the “customer,” you should measure and track your ability to sat-
isfy the customer. If at any time you are unable to achieve the volume, mix, or
sequence that has been defined, it is equivalent to a “missed order” (and repre-
sents a dissatisfied customer, although you may not miss an actual order). You
must train people to consider the heijunka as the voice of the customer and as
a primary objective of the value stream.

Incremental Leveling and Advanced Heijunka

Congratulations! Having gotten to this stage in your lean journey, you’re ready
for the real fun to begin. After processes are stabilized and connected, there is
value stream flow, and improvements are standardized, you now begin the con-
tinuous improvement cycle. That’s right, you get to go through it all again, and
again, and again, forever. The good news is that each successive loop through
the continuous improvement spiral will be somewhat easier, since much of the
foundational learning has been done and resistance to change overcome. Any
changes made from now on will yield direct benefits for the entire process. In other
words, instead of “pocket” improvements that do not affect the overall result,
improvements now will influence the outcome of the entire value stream.
Now the bad news. From here on, the improvement process is a continuous
cycle of “tightening” and refining the operations to achieve shorter lead times
and greater degrees of flexibility and capability, push inventory levels down, and
strengthen the long-term position of the business. Now, the results will be incre-
mental in nature; that is, they will be of a predetermined amount because change
to standardized processes can occur within a defined portion. Because of the sys-
tem that has been created, the desired outcome is identified and the result will
be assured.
The method will stress the value stream, and the weakest link will snap, creat-
ing instability. When the weak link is detected, resources are gathered to attack
the issues. This cycle repeats over and over as shown in the continuous improve-
ment spiral model in Chapter 3 (Figure 3-4). Each successive cycle uncovers
decreasingly smaller problems. So it’s a good news/bad news scenario. The bad
news is that the issues become more difficult to correct. The good news is that
improvements in the process will be significant and your skill level will grow as
the difficulty of issues increases.

Incremental Leveling

After the value stream is connected, the incremental tightening process is applied
to specific points. Remember what happens to the value stream if the produc-