| As a kid I used to substitute in an injection molding plant. We worked for four hours, pause, four hours. The plant ran three shifts, 7 days a week. I worked in a big hall with two rows of molding machines. Each one had a pole with a yellow beacon light at the top. The machines had fixed cycle times and the operator had to repeat the same steps every cycle. For example on one machine I had to put four small metal cylinders into the mould, close the door, wait, open the door and remove the finished parts. Cycle time was only a couple of seconds usually, with the shortest one I remember being 8 seconds. If you were too slow the machine stopped and the yellow light went on. You also could stop the machine on purpose. There was a field with 3 by 6 buttons or something with different stopping reasons, toilet break being one of them. So far, this probably doesn't sound too bad, but to complete picture you have to know two things: 1. Every restart meant throwing away the first one or two minutes of production 2. Foreman had to keep a quota. That meant, yellow light, foreman came and shouted at you. The buttons were never used. You spent four hours straight doing the same routine every couple of seconds without skipping a beat. Whenver I think my job is bad I remember that time and I'm glad for what I have. |
I have worked on production lines and I’ve worked in the manufacturing and quality engineering side of things.
I know a lot of companies do have that old school production at all cost approach, but the better places I’ve worked at have put quality metrics ahead of productivity metrics.
Usually the metrics are safety, quality, delivery, and cost in that priority.
I know Goodhart’s law, “when a measure becomes a target, it ceases to become a good measure,” gets quoted a bunch on HN, but then nothing else is offered up. In my opinion, having these additional metrics with their own targets serves to balance out and constrain a single metric screwing things up. For example, if productivity is going up by producing lower quality parts, this will be shown in either the quality metrics (e.g., scrap rate, yield) or the cost metrics (e.g., material costs have increased, rework costs have increased).
The other component of it all is that the operators can only produce to the level of the systems they have. They can make some small, point improvements to help, but generally there need to be larger process or system level changes supported to make significant improvements.