Ideally, market prices provide all the information needed by firms to make appropriate decisions about what to produce (kind and quality), how much to produce, and what combination of inputs to use in production. A system of perfect markets would deliver the quantity and quality of goods at the time and place necessary to be of highest value to the ultimate consumer. However, the ability of market price to accomplish this task is complicated by a number of factors. In some cases a product attribute that is valued by a user can only be determined by inspection or testing that destroys the product. Some of these attributes may be determined and controlled only as part of the production process and the user must therefore specify the production process to guarantee the quality of the product delivered. The need such additional specifications increases the cost of market transactions, which may include inspection of processes and contract enforcement. These factors complicate the market exchange process and increase the likelihood of a failure of markets to attain the ideal.