I have been able to understand theimportance of identifying variation. The ability to recognise variation either in the process being improved or variation in the people undergoing the improvement process is very key. For process variation, being able to understand what is normal and consistent with a process rather than searching for a non existent reason to alter the process due to just one peculiar or special case. But I wonder if the control limits in companies can be changed? In a situation where the special cause has been identified and eliminated and an adjustment on the control limits is done; if that which acted as a special cause becomes a common cause does that mean the process is stable or more capable? And for people variation, the ability to recognize and be aware of their psychological needs, how it varies fom person to person, their input and the level to which it affects the improvement process is a very significant factor.