People behave differently when there is transparency, scarceness and accountability. For example, there can definitely be a different dynamic at an open bar where no one knows you (or really cares) and a cash bar at a function amongst august colleagues. I’m guessing most of you know what I mean.
Lean behaviors can often be facilitated by the same stuff. A group that I have been working with has implemented a simple, yet powerful improvement idea that illustrates this phenomena within their low volume, high mix business. The improvement was instituted to help gain and maintain stability within their mixed model production kanban system. It also provides insight into the root causes that drive some of that instability.
It seems that representatives of the various downstream customers of the in-process kanban (no batch production in the upstream process, the kanban are satisfied in a FIFO manner) were frequently seeking to move a given kanban to the head of the line…mostly because of their own mismanagement and other barriers. The reshuffle requests were as many as three per shift. It was like an open bar.
Leadership implemented a “passport” system. It’s not really novel, others have applied it. But, it works!
Basically, each of the four consuming departments (with many multiple cells) that are downstream of the kanban are limited to three weekly passes that they can exercise. Each pass entitles the user the opportunity to reshuffle one of the kanbans within the sequence. So, there are rules and there is a finite number of opportunities. No free-for-all here.
There is also also accountability and transparency. The unused passes are hung at a station near the supplying process’ production coordinator workstation. Triggered or used passes are inserted into a locked lexan box so you can see who has been exercising their passes – the name of the downstream department’s production coordinator is printed on their respective passes. See the picture, below.
Oh, and not all passes are the same. They come with different levels of escalation and, perhaps, pain. The first pass is green in color – essentially a “freebie” that can be used for one priority reshuffle. The second pass is yellow in color and requires the supplying department’s manager to sign-off on the pass. This means that a conversation has to occur…with an explanation as to why the pass needs to be triggered. The third pass is red in color and needs the plant manager’s sign-off for it to be accepted. Few folks want to have that conversation – especially if the root cause is/was within their control.
Guess what? The operation is down to about three kanban priority moves per week and a lot less volatility. The system works a heck of a lot better now. Transparency, scarceness and accountability have changed behaviors and provided further insight into other improvement opportunities.