We have identified four different broad classes of focus tasks. It is important to note that using one of the above types within a GBS does not preclude using others. A GBS, depending on its level of complexity, might contain elements of all of these types of focus. It is not crucial to identify which is the main focus. It is useful, however, to identify which focuses are used in the design of a GBS because each one raises a particular set of issues that need to be considered.
Additional focuses mean the designer needs to consider additional questions.