Wednesday, July 25, 2007
Process vs. System Improvement
A couple of days ago I sat in my favorite book café and worked on a Current Reality Tree. Opposite from where I was sitting, a couple with a small child sat down. The man sat at the right table. The woman sat at the left table. (Right and left are from the position of the viewer, i.e me, throughout this article.) After a few minutes, the man rose up, tried to go between the tables, and hit his head on a lamp hanging from the ceiling.
The figure above shows the tables where the couple was sitting. If you look closely at the picture, you won't be surprised that a couple of minutes later, when the man rose up again, he hit his head, just like he did before. The lamps are not centered over the tables, so rising up to the left of either table is likely to result in a bump on the head.
The third time the man rose up, he instigated a process change. Instead of trying to go between the two tables, he went to the right of his table. This time, he didn't hit his head.
Most people would be satisfied with this. Indeed, we do such process changes all the time, little accommodations to work around the imperfections in the systems we are part of.
However, changing just the process left the couple with unsolved problems. One problem is that if there is a small process variation, for example, if the man forgets to move to the right when he rises, he is likely to bump his head again. Another problem is that the woman might bump her head too. As you can see in the picture, the lamp above her table was also off center.
At this time I pointed out the problem with the off center lamps to the couple, and suggested that they should move the tables a little bit to the left. The man grinned (a bit sheepishly) at me, and moved his table, but not the other one. Nor did the woman.
This is very interesting behavior. The man recognized a possible systems improvement when it was pointed out to him, and moved the table. Both he and his partner failed to apply the same solution to the table standing next to it. This is a failure to generalize a solution. They could see the problem with the rightmost table, yet did not recognize that there was an identical problem with the table to the left.
Eventually the couple left, without either one getting bumped on the head. The woman, though she did not implement the systems improvement, i.e. moving the table, did rise carefully, so as not to bump into the lamp above her table.
When they had left, I moved the leftmost table, like this:
In general, we are much better at adapting processes than we are at improving systems. On the other hand, improving systems tends to yield much better results. In this case, all customers sitting down at either of the two tables will enjoy a head-bump free stay at the café. Maybe the café will attract a little bit more business as a result. Customers receiving head-bumps might be less likely to return.
To me, the story illustrates one of the core properties shared by TOC and Lean. Both aim at improving systems. That is why they are so effective. It is also one of the reasons why they are so hard to implement.