Editing Design for Six Sigma (section)

==Distinctions from DMAIC==
Proponents of DMAIC, DDICA (Design Develop Initialize Control and Allocate) and Lean techniques might claim that DFSS falls under the general rubric of Six Sigma or [[Lean Six Sigma]] (LSS). Both methodologies focus on meeting customer needs and business priorities as the starting-point for analysis.<ref>Bertels, Thomas (2003) Rath & Strong's Six Sigma Leadership Handbook. John Wiley and Sons. pp 57-83 {{ISBN|0-471-25124-0}}.</ref><ref name="Chowdhury2002" />

It is often seen that{{weasel inline|date=December 2018}} the tools used for DFSS techniques vary widely from those used for DMAIC Six Sigma.  In particular, DMAIC, DDICA practitioners often use new or existing mechanical drawings and manufacturing process instructions as the originating information to perform their analysis, while DFSS practitioners often use simulations and parametric system design/analysis tools to predict both cost and performance of candidate system architectures.  While it can be claimed that{{weasel inline|date=December 2018}} two processes are similar, in practice the working medium differs enough so that DFSS requires different tool sets in order to perform its design tasks.  DMAIC, IDOV and Six Sigma may still be used during depth-first plunges into the system architecture analysis and for "back end" Six Sigma processes; DFSS provides system design processes used in front-end complex system designs. Back-front systems also are used. This makes 3.4 defects per million design opportunities if done well.

Traditional six sigma methodology, DMAIC, has become a standard process optimization tool for the chemical process industries.
However, it has become clear that{{weasel inline|date=December 2018}} the promise of six sigma, specifically, 3.4 defects per million opportunities (DPMO), is simply unachievable after the fact. Consequently, there has been a growing movement to implement six sigma design usually called design for six sigma DFSS and DDICA tools. This methodology begins with defining customer needs and leads to the development of robust processes to deliver those needs.<ref>{{cite book|last=Lee|first=Sunggyu|editor-first1=Sunggyu |editor-last1=Lee |title=Encyclopedia of Chemical Processing Vol 1|year=2012|publisher=Taylor & Francis|isbn=978-0-8247-5563-8|pages=2719–2734|doi=10.1081/E-ECHP|doi-broken-date=2024-11-11 }}</ref>

Design for Six Sigma emerged from the Six Sigma and the Define-Measure-Analyze-Improve-Control (DMAIC) quality methodologies, which were originally developed by Motorola to systematically improve processes by eliminating defects. Unlike its traditional Six Sigma/DMAIC predecessors, which are usually focused on solving existing manufacturing issues (i.e., "fire fighting"), DFSS aims at avoiding manufacturing problems by taking a more proactive approach to problem solving and engaging the company efforts at an early stage to reduce problems that could occur (i.e., "fire prevention"). The primary goal of DFSS is to achieve a significant reduction in the number of nonconforming units and production variation. It starts from an understanding of the customer expectations, needs and [[Critical to Quality]] issues (CTQs) before a design can be completed. Typically in a DFSS program, only a small portion of the CTQs are reliability-related (CTR), and therefore, reliability does not get center stage attention in DFSS. DFSS rarely looks at the long-term (after manufacturing) issues that might arise in the product (e.g. complex fatigue issues or electrical wear-out, chemical issues, cascade effects of failures, system level interactions).<ref>{{cite web|url=http://www.reliasoft.com/newsletter/v8i2/reliability.htm|title=Design for Reliability: Overview of the Process and Applicable Techniques|website=www.reliasoft.com}}</ref>