GayathriVenkataramani

I used the internet to understand the answer and I am writing. Thanks so much for asking this question so that It is very helpful for me to understand and get clarity. When we do a DMAIC project, we will only consider short term aspects of the data. We also know for the fact that the data will keep varying time to time for the same process and the mean will keep drifting. So when we collect long term data we will experience seasonal impact and specific critical factors impact on the data. Six sigma actually translates to 2 defects per billion opportunity and 3.4 defects per million opportunity. We define as 6 sigma however ends up in a 4.5 sigma value. This difference of 1.5 is considered and to be able to consider the short term impact as well as the long term impact in the calculations that we do, we use this 1.5 sigma shift especially when we calculate one sigma value.

Theoritically we have seven wastes such as "Over production", "waiting", "Excess Inventory", "Rework", "Transportation", "motion" and "Over processing". Additionally people's potential are wasted in many occasions. Having said that, these are some of the ways we can remove these NVAs from our system: - Instead of doing audits , do benchmarking analysis and identify the root causes and fix the problem with a system so that these errors are completely curbed in the future ( System based solutions ) -- Poka yoke. 5 why analysis will be of great help if done diligently. - A clear SIPOC diagram for a process will help identify the wastes explained above so that we can remove these wastes and these SIPOC's should be done frequently. (Offcourse a Value stream exercise will largely help. But when SIPOC is continuously visited major problems can be avoided). Culture development in the organization should be built to ensure that they review the SIPOC and should be able to bring in new ideas to remove these NVAs. If the entry level person in the organization is trained in this manner, his understanding about the system and his contribution will be great. - Always look forward a system based solution to fix the problem. When followed these diligently to greater extent these wastes can be removed.