In a company with separate business units, or different lines of business, that are relatively autonomous in terms of cash management, separate cash flow forecasts may be prepared according to centers of accountability and responsibility. These different business units may be centralized under a single finance function (in a corporate or home office). For example, if a particular unit generates a cash surplus, the central finance function may take this surplus and allocate it according to the business needs of the overall company. On the contrary, if the cash flow forecast of a particular unit shows a cash deficit, the central finance department will know that this unit will require funding.
The general idea is that cash flow forecasts should be prepared where they are meaningful in terms of the information they provide, and where they are useful in terms of the decisions that can be made based on the information the cash flow forecast provides.