The term, producibility, expresses how easily a product can be reliably produced in the desired volume using the existing manufacturing capabilities of a firm. Producibility can be measured in a number of ways, including the time or cost that must be expended to produce the item. Process capability, production yields, and production speed are other attributes frequently used to measure producibility. These measures may be estimated quantities (during product design phases) or actual outcomes (once the product has reached volume production levels). It is important to remember that product producibility is mostly a function of product design. Once the design is solidified, it is difficult to improve producibility.