DT has a great post over at Design Sojourn that discusses Six Sigma methodology and how it relates to design. He cites Tim Brown at IDEO who argues that Six Sigma is essentially Newtonian, while design thinking is quantum. In his own design work, DT expressed doubts about using Six Sigma:
After studying the Six Sigma process, I point blank said: “There was no way any of my designers are going to be judged on the quality and success of a design based on how many sketches or iterations we did before we deliver it.”
Both Brown and DT cite Sara Beckman, who recently discussed the topic in the New York Times. Beckman reviews how Six Sigma focuses on incremental improvements, while design and design thinking focuses on big changes. For those of you who aren’t familiar with Six Sigma, it’s a method pioneered by Motorola, which aims to reduce the number of errors to 3 in one million. The “six sigma” refers to six standard deviations. The number of errors should be at the extreme end of the normal curve, or between + or – 3 standard deviations, represented by the Greek symbol sigma.
I argue that design is more complementary to the “interpretivist” paradigm of qualitative research while Six Sigma is positivist. Interpretivists don’t believe the world is a static place. They see reality as being continuously created by you, me and other social actors. There is no such thing as “The Truth” in interpretivist approaches, just different versions of the truth. Typical methods of interpretivists are ethnography, in-depth interviewing and discourse analysis. Positivist research, on the other hand, assumes that reality is static. Positivists believe that “The Truth,” is out there to be discovered. Typical methods would include quantitative surveys.
Designers should focus on interpretivist methods, therefore. They should uncover different versions of the truth using observation and interviewing, as well as deep reflection on symbols and their meanings. Surveys and other quantitative methods are more Six Sigma in that they can measure improvement over time. Designers ought to consider measuring improvement, but starting with qualitative approaches is best.