What is the purpose of Component Product descriptions
Component Product descriptions govern the development of products/services as well as their subsequent review and approval; as a result they should be mandatory. The level of detail must provide an accurate description and appropriate measure of control sufficient to fulfil the client’s quality expectations.
The purpose of the Component Product Description is to help in planning, requirements development, technical development, quality and approval processes. The detail of the component products is documented in the related User Scenarios and Acceptance Tests.
You can see the collection of Component Product Descriptions as a high level Product Backlog that in combination with the Product Breakdown Structure (PBS) and Product Flow Diagram (Road Map) gives a definitive view of what should be the output of the different management stages and ultimatly the project.
The Component Product Descriptions should be updated by the Senior User / Product Owner to reflect changes in the needs of the client, new ideas or insights, changes in the market, technical issues that appear, etc. Once a Component Product Description has been baselined it is ok to make changes but they should be communicated through the change request process and the new description baselined with an incremental version number
Tip: Some people find it useful to create the component product descriptions iteratively while creating US&ATs, when they first start.