Garbage in, garbage out
We sometimes get the idea that the computer is a panacea, an infallible, virtually intelligent entity incapable of error. The truth is that the computer is just another tool and is only as good as the person using it.
Some years back, I had a guy working for me who was very into computers. He was telling me how the computer could generate my door parts list and then organize it any way I wanted. I could list from largest to smallest or collate all the similar sizes into separate lists and so forth. It seemed like an attractive idea so I let him generate a cut list.
It all worked out the way he said it would and the cutting went much more smoothly than it had it the past. Soon we had a nice stack of door parts, all cut and milled and ready to put together.
But when we to started assembling the doors, the whole illusion collapsed. The parts were all wrong. Very few of the doors were the size they were supposed to be. Panic set in. The spreadsheets were thrown out and we went back to the old way. We were able to salvage some of the material, but it was a costly mistake.
Later, after the dust had settled, I got the spreadsheets out of the garbage and compared them to my hand written list. Sure enough, at least three quarters of the doors were listed with incorrect net measurements. So, of course, the parts were not going to be the correct sizes.
Refer now back to the title of this post.