Defects - The Other Killer Waste
And why you can't inspect quality into your products
Part 5 of Value Creation & Waste; A Lean Practitioner's Perspective
When I recently wrote about Inventory, I called it a 'Killer Waste' because it exists in all types of organisations and is incredibly destructive to capacity. But it is not the only waste to fall into this category. Defects can be simply defined as 'any work that is not right first time'. When not controlled, defects erode capacity, destroy morale, damage customer confidence, waste labour and materials and cause excessive, non-value adding inspection procedures to be implemented. They attack both the top and bottom line of a business. Because of this, I label defects a killer waste and look for them in every client engagement. The common causes of defects are:
• Customer requirements are not properly understood or communicated
• Teams do not properly understand what is and what is not acceptable
• Skills are not developed to the required standards
• Machines, tools or materials are faulty or inadequate
• Work procedures, documentation and training are not standardised
• There is no systematic investigation of defects or implementation of countermeasures
• There is a reliance on inspection alone to pick up defects
I want you to think of two brands: one that you really trust for quality and one that you think has very poor quality. Which one of these do you think does the most inspection? It might seem counter-intuitive, but it is a fact that the organisations producing the best quality work spend by far the least time on inspection. At least an order of magnitude less! Why? Because they don't need to inspect. Instead, they invest in standardisation, robust process and employee skill development so that they don’t make defects in the first place. Or, if they do, they recognise that a defect has occurred, record it and if the defect repeats enough, they carefully investigate to identify the root cause, implementing countermeasures to prevent future occurrence. This takes discipline to implement, and it is this disciplined approach that is a characteristic of lean organisations. This is not to say that you shouldn't inspect at all. If you know you have some vulnerability to defects, it is important to put in some form of gate to prevent them from getting to the customer, but these are usually very specific tests, often automated or done to a checklist, that target the known vulnerabilities of a process. But the long term target should be elimination of defects. It has been long established that inspection can usually only detect defects that you know about and even then some will slip through. Ultimately, you can't inspect quality into products. Much better to get it right first time every time!