Over the course of 20 years, I’ve visited hundreds of different factory floors and seen a wide variety of manufacturers implement data collection and statistical process control (SPC) solutions. I’m often called upon to help establish the proper monitoring strategy to detect changes in a process while allowing for normal variation. Experience has led me to pay particularly close attention to the impact of the most unpredictable factor in almost every process: human beings. Humans are a ripe source of special cause variation, system breakdown or just humorous misunderstandings. I have seen how, sometimes innocently and sometimes deliberately, human actions can result in unwanted outcomes, missed opportunities or head-scratching mess-ups. I thought I would share some of the more interesting or amusing situations that I’ve seen over the years.