The reality in the world is that variation exists. If variation did not exist, if we made a product right the first time, every product would be right the first time. The same would hold for providing a service. But, the reality is that we live in a world where variation does exist and therefore every now and then we will have to deal with a defect, mistake, flaw, or error. Another reality is the variation can be random, meaning that no undue influence is coming from the people, the machinery, the materials, the methods, the measurements, or from the environment. If the variation in a process is random, it is at a state of normality. Other names for normality include common-cause, chance variation, and random variation.