[nickdothutton]

Where to start with this. All I will say is that the job of the Product Manager is if nothing else, to manage the product through the product lifecycle. Concept, development, release, revision, maturity, retirement/death, including likely migration to some new product/service that is a logical replacement. These core duties are most clearly exercised in small product-lead companies. In large firms the job can become very bureaucratic and political as everyone wants to put a hand on the ships wheel, especially if the company is a single-product company.

Edited for typo.