Product-level costs are highest in the introductory phase and generally fall throughout the rest of the life cycle-with possible spikes upward for new models in the maturity phase. An example is engineering change orders, which occur most frequently when the product is started into production. Facility-level costs may or may not be affected unless the product calls for a new facility or equipment-then they are highest in the introductory phase. Exhibit 18.7 depicts the general direction of costs in the ABC categories throughout the product life cycle.