Let's assume your customers requirements are 25 PPM. That means that you would be allowed 25 pieces for every 1,000,000 pieces or 250 defective parts per year. Or to put it another way, one bad part per day! Notice I did not say one bad part per day per person or job, or shift or machine.
The dynamic inheritance allows you to follow open-closed principle by extending classes without modifying existing classes and allows you to choose features that you need at runtime. Of course, dynamic languages such as Ruby make this a lot easier as you can extend classes or objects with modules at runtime, e.g.
Dynamic styles are a key feature of DHTML. By using CSS, you can quickly change the appearance and formatting of elements in a document without adding or removing elements. This helps keep your documents small and the scripts that manipulate the document fast. The object model provides programmatic access to styles.