The availability of software engineering 
Why ask “why?”
availability is built around software development a relatively new trend, it begins with a simple question: Why, why is it necessary why the user to interact with the system? What do they want?
Why ask “why?” Only ask the user why the use of this system, a series of questions to help us focus on the basic elements of the system availability.
Why do some people use the telephone directories ligne.Parce they want to make contact with those they do not know or forget to contact gens.Les key features of the design is incomplete or inaccurate information prepared in accordance system input vigueur.Une good user interface goal of reducing the steps to find the numéro.Pourquoi the user must insert the ATM card? ability to identifier.Avec one magnetic stripe card is sent to sites terminals in a way, more sound waves or infrared scanning to identify calls can also achieve this objectif.Pourquoi in the document the user wants to invoke a dialog for opening certain characters? Because some symbols or characters on the keyboard are pas.Cette dialog will show that some users want to get the character, rather than the existence of the characters on the clavier.Pour identify availability requirements and is at the center of the event to launch a project can save time underway.The architecture of the user interface will be based on these éléments.Les developers can avoid adaptation characteristics of the minimal impact on the availability of wasting time and attention to larger events.