Toothpaste factory

A toothpaste factory had a problem: it sometimes shipped empty boxes without the tube inside. This was due to the way the production line was set up, and people with experience in designing production lines will tell you how difficult it is to have everything happen with timings so precise that every single unit coming out of it is perfect 100% of the time. Small variations in the environment (which can't be controlled in a cost-effective fashion) mean you must have quality-assurance checks smartly distributed across the line so that customers all the way down to the supermarket don't get pissed off and buy another product instead.

Understanding how important that was, the CEO of the toothpaste factory got the top people in the company together, and they decided to start a new project in which they would hire an external engineering company to solve their empty boxes problem, as the engineering department was already too stretched to take on any extra effort.

The project followed the usual process: budget and project sponsor allocated, RFP, third parties selected, and six months (and $8 million) later it had a fantastic solution - on time, on budget, high quality, and everyone in the project had a great time.

They solved the problem by using high-tech precision scales that would sound a bell and flash lights whenever a toothpaste box weighed less than it should. The line would stop; someone would walk over and yank the defective box off of it and press another button when done to re-start the line.

A while later, the CEO decides to have a look at the Return On Investment of the project: amazing results! No empty boxes ever shipped out of the factory after the scales were put in place. Very few customer complaints, and they were gaining market share. "That's some money well spent!" he said, before looking closely at the other statistics in the report.

It turned out that the number of defects picked up by the scales was zero after three weeks of production use. It should have picked up at least a dozen a day, so maybe there was something wrong with the report. He requested an inquiry, and after some investigation, the engineers came back saying the report was actually correct. The scales really weren't picking up any defects, because all boxes that got to that point in the conveyor belt were good.

Puzzled, the CEO traveled down to the factory and walked up to the part of the line where the precision scales were installed.

A few feet before the scale was a cheap desk fan, blowing the empty boxes out of the belt and into a bin.

"Oh, that," says one of the workers, "One of the guys put it there 'cause he was tired of walking over every time the bell rang."