A fundamental reality of application development is that the user interface is the system to the users. What users want is for developers to build applications that meet their needs and that are easy to use.

Too many developers consider themselves to be "artistic geniuses" – while talent may be present, common sense is not, in that they do not bother to follow, or unaware of simple, yet elegant user interface design standards or invest the effort to make their applications usable. Instead, they mistakenly believe that the important thing is to make the code clever or to use a really interesting color scheme. The reality is that a good user interface allows people who understand the problem domain to work with the application without having to read the manuals or receive training.

For most people the
user interface is the software.

Interface design is important for several reasons. First of all the more intuitive the user interface the easier it is to use, and the easier it is to use the cheaper it is. The better the user interface, the easier it is to train people to use it, reducing your training costs. The better your user interface the less help people will need to use it, reducing your support costs. The better your user interface the more your users will like to use it increasing their satisfaction with the work that you have done.

The point to be made is that the user interface of an application will often make or break it. Although the functionality that an application provides to users is important, the way in which it provides that functionality is just as important. An application that is difficult to use won’t be used. Period. It won’t matter how technically superior your software is or what functionality it provides, if your users don’t like it they simply won’t use it. Don’t underestimate the value of user interface design.