Indirect costs are, but not necessarily, not directly attributable to a cost object. It should be financially infeasible to do so. Indirect costs are typically allocated to a cost object on some basis. In construction, all costs which are required for completion of the installation, but are not directly attributable to the cost object are indirect, such as overhead. In manufacturing, costs not directly assignable to the end product or process are indirect. These may be costs for management, insurance, taxes, or maintenance, for example. Indirect costs are those for activities or services that benefit more than one project. Their precise benefits to a specific project are often difficult or impossible to trace. For example, it may be difficult to determine precisely how the activities of the director of an organization benefit a specific project. Indirect costs do not vary substantially within certain production volumes or other indicators of activity, and so they may sometimes be considered to be fixed costs.