Six Sigma

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Six Sigma is a data-driven approach and methodology for eliminating defects and improving quality in any process, from manufacturing to transactional and from product to service. Developed in the 1980s by Motorola, Six Sigma aims for near-perfection in performance, striving to reduce the number of defects to fewer than 3.4 defects per million opportunities. The goal is to identify and eliminate sources of variation in a process to improve predictability and performance.

Core Principles: Six Sigma is built around several core principles:

  1. Focus on the Customer: The primary goal is to deliver maximum value to the customer, which involves understanding customer needs and focusing efforts on meeting those needs efficiently.
  2. Use of Data and Statistical Analysis: Decision-making is driven by data analysis and statistical methods rather than by assumptions or guesswork. This analytical approach identifies the root causes of defects and process variations.
  3. Process Improvement: Six Sigma methodologies focus on improving the efficiency and effectiveness of all business processes.
  4. Active Involvement of Employees: Employees at all levels of the organization are involved in the Six Sigma process, with training provided for key roles such as Six Sigma Black Belts and Green Belts.
  5. Strive for Perfection: Continuous process improvement with the goal of achieving near-perfect results is a central tenet of Six Sigma.

Methodologies: Six Sigma employs two key methodologies:

  • DMAIC: Used for improving existing business processes; it stands for Define, Measure, Analyze, Improve, and Control. This methodology focuses on identifying and eliminating defects in a process.
    • Define the problem and the project goals.
    • Measure current processes and collect relevant data.
    • Analyze the data to identify the root causes of defects.
    • Improve the process by eliminating defects.
    • Control future process performance.
  • DMADV: Used for creating new product or process designs; it stands for Define, Measure, Analyze, Design, and Verify. This methodology focuses on developing processes and products that meet customer needs and achieve high quality.
    • Define design goals that align with customer demands and enterprise strategy.
    • Measure and identify CTQs (critical to quality characteristics), product capabilities, production process capability, and risks.
    • Analyze to develop and design alternatives.
    • Design an improved alternative, best suited per analysis in the previous step.
    • Verify the design, run pilot runs, implement the production process and hand it over to the process owner(s).


  • Improved Quality: Reduces the number of defects and errors in processes and products.
  • Increased Efficiency: Streamlines processes, eliminates waste and reduces variability.
  • Cost Reduction: Lower defect rates lead to decreased waste and rework, which in turn reduces costs.
  • Customer Satisfaction: Higher quality and reliability lead to increased customer satisfaction.
  • Employee Engagement: Involves employees in the improvement process, leading to better job satisfaction and teamwork.