Following User Interface Guidelines
This topic defines what user interface guidelines are and describes why following guidelines exclusively might not be the best strategy.
What Are UI Guidelines?
UI guidelines are collections of recommendations that designers and developers follow when creating the user interface for applications. Guidelines can include:
General design principles derived through research.
These principles can include the expression of a fundamental design philosophy, assumptions about human behavior, a design methodology, and concepts embodied in the interface.
Most, if not all, major software platforms have published guidelines for user interface design. One example is the Microsoft Windows User Experience, which is subtitled the Official Guidelines for User Interface Developers and Designers.
Local rules or style guide.
Many individual companies and organizations have their own set of documented UI rules or styles for interface design that developers in that company use. This is common in large companies especially, where a suite of applications is created internally.
Do Not Rely on Guidelines Exclusively
As an application designer, following UI guidelines helps ensure that the product allows users to apply skills they've already learned to common tasks and learn new tasks more easily. However, you cannot rely solely on guidelines to ensure the usability of your product. UI guidelines are often too general. Yet it's that very generality that makes them difficult to apply. When you are trying to make specific decisions within the context of your product, a general set of guidelines might not give you enough information for you to make a decision. An example is when you're trying to decide between method A and method B of presenting information in a dialog box.
On the other hand, guidelines can be too specific. For example, a guideline might specify having no more than seven items on a menu. However, adding additional menus might be more confusing to users than having more than seven choices on any one menu. Additionally, guidelines may conflict with one another. For example, one guideline might specify having no more than seven items on a menu, and another might specify keeping similar items grouped together on menus. Which guideline takes precedence?
Nevertheless, when designing an application, the visual consistency encouraged by UI guidelines can be helpful. Consider the consistency you find in Microsoft Word and Microsoft Excel. The user interfaces in these software products are very similar in the basic elements such as menus, toolbars, and placement of buttons in dialog boxes (that is, the surface-level interface). In addition, they are consistent in how they handle many common tasks: formatting text, saving files, and so on. Consistency in these and other elements can make it easier for users to transfer skills when learning different applications. Specific UI guidelines can help maintain consistency across different products.
This all boils down to context: A user interface needs to be designed for specific users, goals, and tasks. Guidelines may be a reasonable starting point, but they are only a starting point. The value in UI consistency lies in effective learning, by making it easy to transfer knowledge from another product without interfering with ease of use.