How to Reduce Defects and Variation with Six Sigma

Six Sigma is a time-tested approach that has helped businesses around the world transform themselves and achieved higher levels of customer satisfaction. The ultimate goal of the approach is to identify defects and reduce them.

While many business leaders understand how Six Sigma works at the theoretical level, it’s imperative to understand Six Sigma implementation in the real world for their specific business sector.

What are Defects?

Defects are errors or failures in products, services, or processes. Any problem that causes a product to not function fully can be considered a defect. Defects help identify the problems that need to be addressed, so it is imperative to clearly define defects bothering a business.

A set of specifications and parameters can be established and the variations from those considered defects. The goal is to reduce these variations as much as possible. Sigma denotes process variation and Six Sigma attains a Sigma of 6.0. The result is that fewer than 4 defects occur among a million units. 

Statistically speaking, the deviation of processes from the average is the Sigma. Six Sigma attains three variations above the average value and three below, which greatly reduces the defect rate.

The Tenets of Six Sigma

Six Sigma begins with a relentless focus on the customer and their needs. We need to establish baselines to know what the customer expects from our products and services.

Next, data is collected from a variety of sources to understand where wastes or defects lie in the entire process flow.

We will then aim to address the areas where problems like to reduce the likelihood of defects occurring. 

Six Sigma is a highly structured approach that aims to attain continuous improvement. It’s a continuous process that steers a business in the right direction. The methodology often necessitates a change in the work culture and is highly data-driven at each stage.

How Can I Reduce Defects with Six Sigma?

Six Sigma uses the DMAIC (Design, Measure, Analyze, Improve, and Control) structure to reduce defects and move towards a state of fewer defects. 

Customer complaints, increased costs, and unnecessary rework are often strong indicators of defects. 

Certain departments might be specifically chosen for pilot Six Sigma projects for the greatest positive impact on the business. Oftentimes, this might be a business department that has a consistent history of producing defective units or parts.

Teams will typically conduct a throughout research and collect data from across several touchpoints. Statistical tools are often employed to understand and analyze this data and identify where variations are occurring.

During this phase, the goal is to identify the root cause underlying these defects which the data reflects. This might involve a deep investigation of historical data to get to the core of the problem.

Once the cause of the problems faced is identified, the next step is to design solutions that will address the challenges. Data is once again used to evaluate the efficacy of the solutions and analysis conducted to see how closely the actual implementation of the solution follows the proposed plan.

Techniques like regression analysis might be used to draw useful correlations between the identified causes of defects and the increase in the number of rejected units.

The Control phase follows, where the goal is to sustain the improvements that have been introduced in the preceding step. This involves standardizing processes and methods as well as anticipating the scope for further improvement. Triggers might be created to raise alarms when processes deviate from the expected behaviors.

Solving Problems Using Six Sigma

Six Sigma is fundamentally a problem-solving approach for businesses of all sizes operating in a diverse range of industries. The DMAIC approach will reduce the production of defective products and services and establish a standard framework to stay within acceptable variation limits, in accordance with the core tenets of Six Sigma.

The entire process is highly structured and inspired by data at every stage. The process begins with accurate identification of the voice of the customer, followed by data collection and the use of statistical techniques to analyze the data and draw valuable inferences. Next, innovative methods are proposed to solve problems and the system is standardized to keep the improvements sustainable.