Six Sigma is a system of quality management processes that aims to make operations more effective by reducing defects.
The basic aim of Six Sigma is to make a process 99.99996% defect-free. This means a Six Sigma process produces 3.4 defects per million opportunities (or less) as a result.
While that may seem like a lofty goal, it is attainable. And the more you understand about what exactly a defect is in terms of Lean Six Sigma, the more equipped you are to achieve that defect percentage.
Overview: What are Defects (%)?
Defects are a fundamental part of the Lean Six Sigma process. Defects are defined as anything that does not meet the customer’s requirements, including defective materials, manufacturing errors and deviations from standards. They are one of the main categories of waste identified in the Value Stream Mapping process and occur when products are not up to standard and must be fixed before they can be sold or used. Because defects cost money and time, it’s important to keep them to a minimum by implementing processes that minimize their likelihood and impact.
There are two types of defects: Internal defects and external defects. Internal defects occur during production or delivery of a product or service; they are caused by the manufacturer or supplier. External defects are caused by the customer or end user of a product or service; they occur after production has been completed but before delivery.
3 Drawbacks to Defects (%)
Lean Six Sigma is a management system that aims to reduce waste and increase quality, speed, and cost-effectiveness. It’s based on the idea that defects can be reduced by identifying and removing them before they reach customers. While their existence can ultimately reveal a problem you can then correct, they are considered to be a wastes of time, money, and resources.
The noteworthy drawbacks are:
1. Defects are costly.
There are several reasons for this. First, the process itself is costly because it involves a lot of data collection and analysis. Second, it takes time to figure out what went wrong and how to fix it, which can lead to delays in production or other processes. Third, when a defect occurs, it has to be tracked through the entire system, which can also slow down production or other processes. And fourth, defective products can potentially cause injury which can lead to lawsuits.
2. Defects lead to a decrease in customer satisfaction.
This can lead to a significant loss of revenue. If a defect is found after the product has been shipped, then it is too late to do anything about it. The customer may return the product and demand their money back. This can cost millions of dollars in lost revenue for a company that relies heavily on sales.
3. Defects can lead to decreased productivity at work.
This is due to lost time spent fixing problems caused by poor quality control standards within your company’s manufacturing processes which were supposed to prevent these kinds of issues from happening during production runs in the first place. When human error makes that impossible, you can run into even more problems than ever before and get caught in a problematic cycle with no real solutions in sight.
Why are Defects (%) Important to Understand?
Defects in Lean Six Sigma are important to understand because they help identify problems in your process. Defects can be anything from a small error, like a typo, to a large problem such as an incomplete or incorrect data set. When you know how many defects occur in your process, you can use this information to improve the efficiency and effectiveness of your organization.
Defects also cause a lot of problems and waste in an organization. They can cause customer dissatisfaction, loss of revenue, damage to reputations or standing within the industry, loss of market share, and even the demise of the business.
Most importantly, you cannot eliminate a problem if you do not understand what is creating it, and what it will take to effectively remove it.
An Industry Example of Defects (%)
There are few industries, if any, where defect management is more important than in healthcare. Hospitals in particular are constantly striving to lower their defect rates. Successful hospitals that have been in existence five years or more have an average defect rate of about 1%. Even the most basic LSS tools can help a business achieve this. But once this percentage is reached, and more improvement is desired, more exotic tools in the framework are needed.
Key tools for defect reduction in healthcare facilities include:
Pivot tables – Pivot tables help reduce defects in LSS by aiding the process of identifying problems, demonstrating progress and plotting possible solutions. They allow easy comparison of defects and other metrics over time.
Control charts – Control charts are one of the most important tools for reducing defects in lean six sigma. They help you to see how much variation there is in your process, and whether or not you can plan on consistent results.
Pareto Charts or Histograms – Pareto charts and histograms are very useful in reducing defects in Lean Six Sigma. They can help identify which areas of a process need the most attention when it comes to improving quality, and they can also help identify if there are any outliers (data points that are significantly different from the rest of the data).
Fishbone Diagrams – Fishbone diagrams are used to identify all possible causes of an issue and help you evaluate which ones are most likely to be causing the problem.
With these tools, medical facilities have been known to reach defect rates of 0.03%.
3 Best Practices When Thinking About Defects (%)
Six Sigma as a discipline has a focus around variation. More specifically, ultimately reduction and control over variation in a process. Best practices for successfully achieving Six Sigma standards include:
1. Before anything else, ensure you have a solid understanding of what Six Sigma actually is.
Six Sigma describes a target of 3.4 defects per million opportunities which is considered to be world class.
Sigma is the term given to a measure of deviation in a data set. Plus or minus six standard deviations around a central tendency covers 99.9997% of the data within a data set. If those plus or minus six standard deviations sit within the customer specifications, then you can say the process is Six Sigma capable. In other words, your process is generating no more than 3.4 defects per million opportunities that arise in relation to the customer specifications set.
2. Hire at least one Black Belt or Green Belt who understands Six Sigma and is passionate about your organization’s goals.
A Black Belt or Green Belt can provide valuable insight into the process, and will act as a liaison between leadership and employees. They are often tasked with conducting planning sessions prior to implementation of projects. They also serve as training guides who lead employees through new improvement initiatives.
3. Seek out other businesses that have already reached the pinnacle of Six Sigma performance.
When other companies are able to achieve this, it can be valuable for the business looking to implement Six Sigma to learn from the methods and steps that were used by these businesses prior to their success. By learning more about where these companies struggled initially and how they overcame those obstacles, your organization can reduce the difficulty of achieving Six Sigma standards.
Frequently Asked Questions (FAQs) About Defects (%)
How is a defect measured?
A defect is measured in Lean Six Sigma using the DPMO (Defects Per Million Opportunities) metric. This metric is used to determine the number of defects per million opportunities that a process has to produce a product that meets customer requirements.
How can you tell if your organization is succeeding with defect reduction efforts?
To assess whether your organization is succeeding with defect reduction efforts, you should look for two things:
1. A reduction in defects per unit (DPU). DPU is calculated by dividing the number of defects by the number of units produced.
2. An increase in the percentage of defect-free units produced. If there is an increase in the number of defect-free units produced compared to the number of defective units produced, then you are likely succeeding at reducing defects.
What are the most common types of defects that occur in Lean Six Sigma projects, and what causes these problems to happen more frequently than others?
There are a lot of different types of defects that can occur in Lean Six Sigma projects, but the most common are those that involve data collection and analysis.
There are several reasons for this, including:
1. Data collection and analysis is often done manually, which means it’s vulnerable to human error
2. The data may be collected incorrectly or incompletely by the people who collect it
3. Management doesn’t always understand the importance of data collection, so they don’t always prioritize it as much as they should.
A Concept to Make Every Business Better
This defect reduction concept should not be foreign to anyone in the business world today. While achieving the desired percentage rate can take some time and effort, the overall concept is simple, and the question of whether or nor your company needs to consider such efforts is a no-brainer: regardless of the industry you are in, your business should always be striving to reduce defects in order to simply become better.
