Mistakes versus Defects: Feedback Is the Cure (Again)

Shingo differentiates between mistakes, which are inevitable as part of the nature of human beings, and defects, which are mistakes that manage to get through the system and reach the customer. Poka-yoke seeks to prevent mistakes from becoming defects.

In the context of software development, we use the catchy word bugs to identify defects, and the test suites are our poka-yoke.

So the key enabling factor in preventing defects is having a mechanism to gather feedback in our processes for all the important aspects of development. The quicker the feedback, the more effective, because identifying mistakes early is what prevents the waste of working on an incorrect product and sending it downstream.

If you see things in this way, most of the activities we do, be they methodological or technical, derive from an agile mindset and are oriented to gathering quick feedback for the different aspects of our work.

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