Encontrei um texto muito interessante, entitulado Revenue Products need Product Managers, not Product Owners, sobre as responsabilidades dos gestores de produtos. O texto inteiro é controverso pois reduz o papel do product owner a um subcojunto do papel de gestor de produto.

O que gostei desse texto é a definição do papel do gestor de produto:

Product Managers bear primary responsibility for the success of their products (services). They drive vision, roadmaps, target segments, market success metrics and customer acceptance. When executives demand one neck to choke, a Product Manager steps forward.

Product managers serve three distinct constituencies: technical teams (who build products), marketing/sales teams (who deliver customers and revenue) and executives (who drive strategy and resources):

• Development teams need vision, requirements, priorities, personas, user stories, and market information from Product Managers. They collaborate on release plans, roadmaps and architectures. In return, Development produces working software and finished products.
• Sales and marketing teams need customer-oriented materials, messages, pricing and strategy. They pass these through to customers. Customers are benefit-focused instead of feature-obsessed, demanding simple information and clear usage scenarios. Responses from customers are often unflinching critiques of the products we love.
• Executives manage the company’s portfolio of products and people. They need roadmaps, revenue and resource forecasts by product, and competitive intelligence.

In return, they give Product Managers permission to pursue selected markets.
Thus Product Managers bridge between developers, markets and executives. This requires skills as a simultaneous translator, reformulating information for each audience. Most importantly, the Product Manager represents the customers to each internal organization.