Which term refers to a quality program focused on reducing process variability and defects per million opportunities?

• A. Lean manufacturing
• B. Six Sigma quality
• C. Total Quality Management
• D. Quality control

Answer: (B)

Reducing process variation and defects per million opportunities is what Six Sigma quality is all about. This program treats defects as a statistical problem and uses data-driven methods to identify and remove sources of variation, aiming for a level of quality near perfection—often quantified as about 3.4 defects per million opportunities. It follows a structured improvement cycle, typically Define, Measure, Analyze, Improve, and Control, to improve existing processes and sustain gains.

Lean manufacturing, while focused on eliminating waste and improving flow, doesn’t center on the precise, statistically driven reduction of defects per million opportunities. Total Quality Management is a broader organizational philosophy about building quality into every facet of operations and culture, not the specific statistical program that targets variation and defect rates. Quality control involves inspecting outputs to detect defects, rather than systematically reducing variation throughout the process.