How Kanban Breaks Down
Last summer, I wrote here about everyday examples of Lean. In one entry, I described my Jugban system of keeping distilled water in the house for my contact lenses. A simple container Kanban system, it just works.
Or so I thought until I saw how kanban breaks down.
My clever system for refilling the empty container involved a nearby grocery store having a distilled water dispenser that worked. Alas, the dispenser was out of service recently. So, I went to another grocery store nearby which also had a dispenser. That helped me out for a few weeks. And then IT broke down! I was in a pickle and ended up having to buy a new gallon at a drug store.
Kanban works marvelously so long as the supplier can and will consistently supply the requestor with the exact amount requested at the time requested in the quality required. When the supplier breaks down or becomes unreliable, you have three choices. Fix the supplier. Change the supplier. Increase your buffer inventory.
Or else your vision really clouds.