A toothpaste factory had a problem: they 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 their 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 they 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 would weigh less
than it should. The line would stop, and someone had to walk over and
yank the defective box out of it, pressing another button when done to
re-start the line.
A while later, the CEO decides to have a look at the ROI 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 says, before looking closely at the other statistics
in the report.
It turns out, the number of defects picked up by the scales was 0
after three weeks of production use. It should've been picking up at
least a dozen a day, so maybe there was something wrong with the
report. He filed a bug against it, and after some investigation, the
engineers come 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 travels down to the factory, and walks up to the part
of the line where the precision scales were installed.
A few feet before the scale, there was a $20 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".
