The ability of any website or a web application to attract and engage users ultimately depends on how well the user interface is designed. Even the best developed service or product will be a failure if the user finds it to be too complicated to navigate or too confusing and feels it is monotonous or unattractive. A good user interface allows the user to carry out the intended actions efficiently and effectively, without causing too much of a distraction. User interface is the only way you can communicate with your client accessing your site remotely.

A good UI should be able to achieve business goals while keeping in mind the requirements of the user providing excellent UX to the user. Providing good User Experience is invariably an important component of a good UI.

The points to be kept in mind while designing good user interface are:

1. Clear and Simple : A good user interface provides a clear understanding of what is happening behind the scenes or provides visibility to the functioning of the system. The whole purpose of user interface design is to enable the user to interact with your system by communicating meaning and function. Obviously, if the interface too complex to navigate, it might annoy the user and make him or her leave the page quickly and move on to some thing else. Make sure the interface is understandable and simple to navigate through.
2. Creative but familiar : When the users are familiar with something and know how it behaves, navigation becomes easier. In effect, the user expects to see what is familiar to him or her. It is good to identify things that your users are accustomed to and integrate them into your user interface. At the same time, users appreciate some thing creative, not so run-off-the- mill experience. But while being creative it should be kept in mind not to lose the familiarity component.
3. Intuitive and consistent : The controls and information must be laid out in an intuitive and consistent way for an interface to be easy to use and navigate. It’s not good to drastically change the lay out to achieve the changing functionality the business may require from time to time. The design process should be based on the logic of usability -features that are the most frequently used should be the most prominent in the UI and controls should be made consistent so that users know how to repeat their action.
4. Responsive : If the interface fails to keep up with the demands of the user, this will significantly diminish their experience and can result in frustration, particularly when trying to perform basic tasks. Wherever possible, the interface should move swiftly in pace with the user. Being responsive means being fast. The interface, if not the program behind it, should work fast. Waiting for things to load might make the user frustrated.
5. Maintainable : A UI should have the capacity for and changes to be integrated without causing a conflict of interest. For instance, you may need to add an additional feature to the software, if your interface is so convoluted that there is no space to draw attention to this feature without compromising something else or appearing unaesthetic, then this signifies a flaw in design.

The better the user interface the easier it is to guide people to use it and it also reduces the training costs. The better your user interface the less help people will require exploiting it and keep them coming back.