What is the purpose of Avaya's 'User Interface Design Guidelines'?

The purpose of Avaya's 'User Interface Design Guidelines' is primarily to standardize the development of user interfaces. By following these guidelines, developers can create consistent, user-friendly experiences across various applications and platforms. This consistency not only improves usability but also helps in maintaining a cohesive brand identity across Avaya's offerings.

Standardization in the design process ensures that all interfaces adhere to specific usability principles and design patterns, which can lead to increased efficiency in development and a reduction in learning curves for end-users. When users encounter familiar design elements, they can navigate applications more intuitively, resulting in a better overall experience.

While aesthetics, usability testing, and marketability are significant in their own right, the core objective of the design guidelines is to establish a uniform approach to user interface design, making option B the correct choice.