In my trainings I always explain the principle that teams pull their work from the backlog by using the metaphor of a supermarket. I do not do this because I find this picture so cool, but because it is the original root of the idea. Steering a production line based on the idea that the requester will request and receive exactly what they can consume.
Ohno went to the United States to visit automobile plants, but his most important U.S. discovery was the supermarket. Japan did not have many self-service stores yet, and Ohno was impressed. He marveled at the way customers chose exactly what they wanted and in the quantities that they wanted. Ohno admired the way the supermarkets supplied merchandise in a simple, efficient, and timely manner.
In later years, Ohno often described his production system in terms of the American supermarket. Each production line arrayed its diverse output for the following line to choose from, like merchandise on supermarket shelves. Each line became the customer for the preceding line. And each line became a supermarket for the following line. The following line would come and choose the items it needed and only those items. The preceding line would produce only the replacement items for the ones that the following line had selected. — Toyota Motor Manufactury Kentucky
We, everyone who wants to make product development teams more effective, must understand that the pull principle has to be respected and used. Most debates in classes I run are because people can not see that this will be possible in their daily lives.
Managers must understand that pushing people harms the effectiveness of their people – it is the root cause of most problems in companies.