Firstly, services are often an input into the production process, as the examples of telephone services or accounting illustrate. Due to the fact that such input services can be vital to the development of certain parts of the economy, one could argue that without adequate input service provision, certain parts of the economy may never grow at all. Adequate service provision can, therefore, at times be vital in developing an economy in a manner that goods cannot be. Another important difference between goods and services is that “services tend to be differentiated products, whereas some goods are homogenous in nature and other goods are differentiated” (Kerr 2008: ppp. 151). As one can see, thereforethere are, there aretherefore, a number of important differences between the evaluation of goods and services. It is important now to move on to discuss why these differences between goods and services exist in the first place. As has already been noted above, the major difference between goods and services is the fact that goods are tangible products, whereas services tend to be intangible in nature. The differences between the two concepts are clearly illustrated by the example of the Concept Development Corporation. In the final section, it is important to consider the consequences of the differences between the two products of the Concept Development Corporation on concept evaluation techniques and/or methods. It is clear, that, due to the fact that goods and services are different in nature, different techniques must be employed in order to evaluate the two concepts. For example, in order for a customer to evaluate the extent to which a good is soundly constructed, they may want to stress-test the product to ensure that it can withstand external pressure inflicted upon it. This type of test would not be applicable to a service.