Issues and groups - best practice
We are told that it is really important to get the Issues and Groups hierarchy sorted right at the start of a project because it is difficult to change or to move groups from one issue to another. However the training does not give us any best practice, or criteria, or method for designing a good Issues and Groups hierarchy based on an analysis of the customer's business.
Is there any documentation or any other source where this topic is covered in detail with real-life examples?