In the development of software systems, software engineers argue over the description of a new product.  This argument primarily occurs over the maintenance of existing systems and how to test them.  For a few system thinkers, any alteration to a software product establishes a new system because the alteration establishes a new experience of that product.  For others, the purist, a software product becomes a new product only when it is first designed.  Subsequent changes are only versions of an existing product.  Depending on perspective, both are correct.