THE FENCE

English author G.K. Chesterton once wrote about the paradox of the fence. He asked the reader to suppose that they were walking down a road and came upon a fence across it. The walker could see no logical reason for the fence and their first reaction might be to tear it down. Chesterton says that this is exactly the wrong response. The fence did not appear by magic, someone put it there for a reason. It may not have been a good reason and perhaps the fence should be torn down. However, until the reason is known, no action should be taken.

Back around 1980 a local plant began requiring that all cars be parked in reverse. About 10 years ago a new manager came from Europe and asked why this was. He was given a number of suppositions (“So we can evacuate in case of a hurricane?” was one) but no good answer. The manager’s reaction was that the policy made no sense and he was going to eliminate it. I heard about this, and knowing the original reason, was able to pass it along. Once he understood, he left the policy in place. (The reason is safety. An accident is more likely to occur when backing out of a space at the end of the day than when backing in the morning.)

Sometimes the reason is not so good. I like the story of the roasting pan: Briefly the daughter always cut off the end of the ham, because her mother had taught her to. The mother had been taught by her mother. She did it originally because her roasting pan was too small and it got carried down through 2 generations.

I work in a lot of different plants and I am constantly asking “Why is this being done this way? Or at all for that matter”? Many times there is no good answer. It made sense years ago and continues because nobody has ever questioned it.

Sometimes though, as with the parking, it made sense years ago and still makes sense today but the reasons have been lost to memory. If the reasons are not understood, elimination can do more harm than good.

Packaging machinery can be like that. Sometimes it is difficult for the mechanic (or other technician) on the plant floor to understand the reasons for certain machine design features. They may see a machine part or a line in the PLC code that serves no obvious purpose and eliminate it. They may be right to do so. But they may also be wrong.

The key is to make sure that anyone who works on a machine must first understand it. They must understand how it works but they must understand the why behind the how. They need to get into the designer’s head and understand what he or she was thinking. I find that too often in mechanic training this understanding of the system is overlooked or minimized. Training must be deeper than simply “If A happens, do B.”

Competent and experienced mechanics will have less trouble understanding a machine or system. Hopefully, they will be more aware of the need for this understanding and be willing to take the time to think it through. This is not always the case.

The reasons why a machine works the way it does must always be understood and training must be done with this in mind.