Most organisations use a year, rather than a week or a month, as the period over which to calculate budgeted cost-driver rates. This is because for the longer the time period, the reason, the the influence of seasonal patterns, and for reason, the longer the time period, the the effect of variations in output levels on the allocation of fixed costs. -costing may result in overpricing and competitors entering a market and taking market share for products that a company erroneously believes are low-margin or even unprofitable. -costing may result in compdies selling products on which they are in fact losing money, when they erroneously believe them to be profitable