DPMO is the core six sigma concept. A defect occurs when a product or service is outside specification...As Bill Smith, the hero of six sigma, ironically pointed out, the specification can be anything you want it to be. DPMO can hence be anything you want.
It was the snake oil sales men who bastardized his - and other's - concepts - but they did make a lot of money:
It has been a great line for consultants approaching senior managers to say "I can absolutely guarantee that I will reduce your defect rates ! " How how impressive is that ... at least for anyone who has no understanding of the basics of quality. Approaches such as this have been used to milk companies of billions of dollars.
Sure it's fun....but still....
You may find occasions when one side is right and other situations when the other side is right. This just happens to be one example...
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