This paper presents an analytical study of the non-functional requirement (NFR) usability with the objective of showing how they can interfere on the quality of a product. It differs from other articles once it presents an analysis of two sites: the Brazilian "<a href="http://ingresso.com.br/" target="_blank">ingresso.com.br</a>", first ticketing company established in Brazil and the multinational "<a href="http://www.ticketmaster.com.br" target="_blank">ticketmaster.com.br</a>", one of world's leading ticketing company. These sites were chosen because the success of these companies relies, in part, on its ability to establish and maintain optimal communication with their clients. To perform this analysis, it was used a taxonomy that describes, enumerates and classify the requirements; then it compares the sites to verify which offers better usability. This paper describes characteristics that should be considered during the design of an e-commerce site, enhancing the importance of the NFR usability.
Usability; web based information systems; virtual companies
