8.4 Cost drivers
The industrial world has realised that overheads do not just happen; they are caused by something, some activity that drives the costs. It is now recognised that direct labour hours is no longer the primary cost driver . Cost drivers are the activities of a business, which cause costs. If managers can identify the cost drivers or the activities, which are causing the costs, they can evaluate whether these activities are needed and whether the cost of the activity is justified by the benefits derived.
Supporters of activity based costing argue that most overheads can be analysed and cost drivers identified. Managers then have a clear insight into the costs incurred by the activity that causes them, and so can allocate these costs to particular jobs more fairly and accurately.
There is no real difference between the traditional approach to allocating overheads and ABC. ABC is concerned only with the way in which overheads are allocated to particular jobs in order to derive full cost.
ABC does have some shortcomings. It can be time consuming to identify all of the different activities that drive costs, and the cost of doing this task may be greater than the benefits derived from using it.