How is Poka Yoke different from FMEA?

Software QA is not about finding mistakes in a code. It is about enhancing the quality of the product to meet objectives while delivering consistent performance at a higher level.

Whether the project is in the analysis phase, design mode or the implementation stage, there are different types of software QA practices that are followed by organizations in recent times. These ‘mistake proofing techniques‘ reduce errors at the development stage. One such practice that doesn’t allow mistakes to happen is Poka-Yoke.

Honestly speaking I personally did not get the opportunity to implement any of these so-called QA processes formally, but based on some research/readings done recently, am excited to share some interesting points.

What is Poka-Yoke?

The Japanese term Poka-Yoke, introduced by Shigeo Shingo, is a mistake-proofing technique that eliminates inadvertent errors. Literally, Poka means mistake and Yoke means to prevent. In simpler words, it talks about preventing mistakes. It is a safe practice that uses an automated system to disallow errors or alert you when an error occurs. By eliminating human data input errors, this mistake-proofing technique allows businesses to fail-proof the system. The rear part of a CPU is an example of Poka-Yoke systems wherein each port comes in different sizes and colours to make the assembling task easier.

Initially, Poka Yoke was designed to implement mistake proofing techniques in the manufacturing industry. A SIM card slot that does not allow you to insert the SIM in a wrong way is a good example of this concept.

Today, the modern software development segment is greatly in love with this innovative concept. The increasing popularity for this concept is because web applications are created in huge numbers in recent times. While these web applications are designed with self-explanatory help content, there are several people who make mistakes while feeding data or using navigation features. For instance, the password field warns you when you enter characters less than 8.

What is FMEA?

‘Failure Mode and Effective Analysis‘ or FMEA is an analysis that helps you identify root causes of defects in a product, in the design stage or in the production stage.

In other words, failure mode refers to areas wherein the product can fail and the effective analysis refers to the effect caused by each failure. When a defect is identified, remedial methods are suggested. By implementing these changes, businesses can eliminate defects in the functionality of a product. As this is an on-going process, FMEA is documented and followed throughout the life of the product.

How is FMEA different from Poka-Yoke?

While FMEA is an analysis that identifies root causes of product failures using a top-down analysis, Poka-Yoke is a technique that makes the product fail-proof. Both of these procedures work similar to some extent as they envisage and identify detects in a product. However, Yoka-Poke is more about human failures that can occur due to lack of knowledge, fatigue or carelessness. FMEA documents may contain Poka-Yoke techniques.

The increased use of Poka-Yoke systems in recent times has effectively reduced errors in product functionality caused by various issues. On the other hand, FMEA envisages these errors at the development stage to eliminate them. By suggesting remedial measures, FMEA ensures that these mistakes are not carried into the development phase. As the entire project specifications are determined before the development takes off, it is critically important to identify any issues with the product in the early stages to avoid expenses. In fact, FMEA identifies areas wherein Poka-Yoke is required. So, FMEA and Poka-Yoke techniques work well when they are perfectly coordinated in product development projects to save time and money.

Be it Poka-Yoke, FMEA or any other software QA practice, businesses need to ensure that highest quality is maintained while developing a product. By ensuring that best software development practices are followed throughout the software development lifecycle, businesses can optimize resources while improving productivity levels.