“All too often, we overproduce – We simply do more than is necessary.”
All too often, we overproduce. We do more than is necessary, we do more than the next person wants, needs or can cope with, and we end up with a pile of inventory.
The lean concept of pull builds on the idea of “process flow”. If we continually flowed products we would without a doubt, end up with inventory as we produced more than the customer wanted. The same is true of individual processes, as well. At some point, one process may flow so well that the next team or department can’t cope with the speed of the flow, and we would end up with a pile of inventory. We would overproduce.
The way to get around this is that we must start at the end of the process – with the customer. We then have to design what we do around customer demand. If the customer does not take a can of baked beans off the supermarket shelf and scans it at the till, no one will try to fill the supermarket shelf up with replacement tin. No one would order a replacement from the regional distribution centers. And the regional distributor centers will not order another replacement from Heinz (or any ofter not so good brands).
At it’s heart, this is the concept of lean pull (and kanban). We have a steady supply of materials ready to be pulled by the next process step. When the customer “pulls” the material forward, there is a signal to the previous process to produce whatever was taken.
The goal, just like flow, is to create a steady stream of products flowing to the customer based on the customer demand with small quantities throughout the process.
If you apply the supermarket idea to your home shopping, how many of us do a weekly bulk shop? We buy what we think we might want only to inevitably have more in the fridge than we can use, and some of it ends up in the recycling. Buy 2-get-1-free works entirely for supermarkets. We think we get a better price, but overall – does it work for our household budgets and the amount we put into the trash.
The key when trying to create “pull” or perhaps “implement pull” is to work on processes that are as close to the end customer as possible first. There is no point in making the “pull” work correctly, only to pay for increased finished goods storage.