Donna was perturbed, “We have a real problem with consistency. I think everything is going okay and then boom, we get hit with a warranty event that uncovers a whole batch of bad product. I already have two people doing random inspections prior to shipping. Still, mistakes get through. I might have to add more inspectors, check everything, just to keep bad product off the shelves.”
“What do you do with the bad product?” I asked.
“Well, we can’t sell it and we can’t melt it down, so we throw it away,” replied Donna.
“Have you used your bad product to isolate the problem production area?”
“Oh, we know the three areas where we have problems, but rather than pull bad product in three places, I thought it best to inspect just before shipping so we can pull all the bad product at the same time, no matter where the problem occurred.”
I winced. “Donna, the purpose of Quality Control is not to pull bad product. The purpose of Quality Control is to identify where the problem is and fix the problem. Consistency doesn’t come from pulling 3 percent of your production. Consistency comes from adherence to systems. The bad product points you to the right area, but when you get there, you have to inspect how processes and people are adhering to system standards. Reduce bad product so you don’t have to pull it.” -TF