INTRODUCTION TO SOFTWARE DESIGN FOR SIX SIGMA (DFSS) - Software Design for Six-Sigma: A Roadmap for Excellence - page 180

I-denfy C-onceptualize O-pmize V-erify & Validate

FIGURE 8.3 The ICOV DFSS process.

champion (if necessary) conduct reviews called “tollgate” reviews. A development
stage has some thickness , that is, entrance criteria and exit criteria for the bounding
tollgates. The ICOV DFSS phases as well as the seven stages of the development
process are depicted in Figure 8.3. In these reviews, a decision should be made whether
to proceed to the next phase of development, recycle back for further clarification
on certain decisions, or cancel the project altogether. Cancellation of problematic
projects, as early as possible, is a good thing. It stops nonconforming projects from
progressing further while consuming resources and frustrating people. In any case, the
Black Belt should quantify the size of the benefits of the design project in language
that will have an impact on upper management, identify major opportunities for
improving customer dissatisfaction and associated threats to salability, and stimulate
improvements through publication of DFSS approach.
In tollgate reviews, work proceeds when the exit criteria (required decisions)
are made. As a DFSS deployment side bonus, a standard measure of development
progress across the deploying company using a common development terminology
is achieved. Consistent exit criteria from each tollgate with both software DFSS
own deliverables from the application of the approach itself, and the business unit
or function-specific deliverables. The detailed entrance and exit criteria by stage are
presented in Chapter 11.

8.6 DFSS VERSUS DMAIC

Although the terminology is misleading, allowing us to assume that DFSS and Six
Sigma are interrelated somehow, DFSS is in its roots a distinguishable methodology
very different than the Six Sigma DMAIC because it is not intended to improve but
to innovate . Moreover, in opposition to DMAIC, the DFSS spectrum does not have a
main methodology to be applied as is the case for Six Sigma but has multiple different
processes and templates. 7 The one we adopt is ICOV as discussed earlier. However,
the objective is the same: a newly designed product with higher quality level—a
Six Sigma level of quality. The ICOV DFSS approach can be used for designing of
products (Yang & El-Haik, 2003), services, or processes (El-Haik & Yang, 2005)

7 See Section 8.7.