Projects are the way that most new work gets delivered. Projects can be managed using a common set of project management processes. For instance, all projects should be defined and planned, and all projects should have processes to manage scope, risk, quality, status, etc.
Products on the other hand, are tangible items that are produced by a project. Project management can be thought of as a process. A product is delivered by a project. Product management is an approach for centrally coordinating the activities surrounding the long-term support and enhancement of a product. The person that executes these responsibilities is called a Product Manager.
The role of a Project Manager is to plan and manage a project. The role of a Product Manager is focused on the long-term support of the product within the organization. The product management role includes the following responsibilities.
Coordinate product issues
Primary contact with the product vendor
Monitor product direction with the vendor
Determine which components of the product should be used
Coordinate testing of new products and releases
Determine when a product is production-ready based on testing and pilot projects
Coordinate certification of new products and releases
Coordinate product contracts, purchase agreements, and maintenance agreements
Ensure that budget is available for product purchases and maintenance
Product Implementation and Deployment
Coordinate development of a product deployment plan
Manage deployment of the product or new releases
Track product inventory (where the product has been deployed)
Receive ongoing requests from the staff for individual product deployment
Product Release Management
Decide when to upgrade the product to new version
Plan and manage new release implementation
Determine when product needs to be retired
Plan and manage product retirement
This process covers a product from its inception until the product is no longer viable.
Product management is hard. Project management is also hard but at least there are many methodology products and tools to assist.