I have worked in production most of my life, and one thing I have learned is that we will never make a product that is 100% defect-free. There will always be some level of defects in production. That is simply part of the process.
We have to be careful not to fall into the trap of believing that all defects can be eliminated or that something must be fundamentally wrong every time an error occurs. Dealing with defects is part of the work of running a business, and it needs to be planned for.
The first reason is economic. As you get closer to zero defects, each additional improvement becomes more expensive than the last. The effort required to remove the final defects often grows disproportionately to the benefit received. At some point, the cost of prevention exceeds the value of eliminating the defect. Organizations have to decide where that point is for their industry, customers, and products.
Even methodologies known for their focus on quality recognize this reality. Six Sigma, for example, does not assume perfection. Instead, it aims for approximately 3.4 defects per million opportunities. The goal is not zero defects. The goal is to reduce variation, improve consistency, and keep defect rates at a level that meets business and customer requirements.
The second reason is that not every defect signals a systemic problem. Sometimes mistakes happen even in healthy processes. A single error should not automatically trigger a major process overhaul.
At the same time, we cannot use this reality as an excuse. Some defects do point to systemic issues that need to be addressed. The challenge is distinguishing between normal process variation and problems that indicate the process itself is broken.
This is where judgment matters. You do not want to waste resources chasing every isolated error, but you also do not want to ignore patterns that suggest a deeper issue. The goal is not the absence of defects. The goal is keeping defect rates within acceptable limits for the business and ensuring that defects are detected as early as possible.
Even the systems designed to catch defects are imperfect. Inspections, reviews, audits, and testing processes can all fail. That does not mean they are useless. It means that quality management, like production itself, is an ongoing balancing act.
A healthy organization recognizes two truths at the same time: defects will occur, and reducing them is still important. The objective is not perfection. The objective is to build processes that consistently produce acceptable outcomes, identify problems quickly, and improve when the data shows improvement is needed.