Which design principle emphasizes making a solution straightforward for users to navigate?

The design principle that emphasizes making a solution straightforward for users to navigate is indeed ease of use. This concept focuses on creating user interfaces and experiences that are intuitive and simple to understand. When ease of use is prioritized, designers aim to minimize cognitive load on users, allowing them to complete tasks efficiently without confusion or unnecessary effort.

Ease of use often involves streamlined processes, clear navigation paths, and user-friendly features that enhance the overall experience. This helps to ensure that users can interact with the solution without having to spend excessive time learning how to use it, leading to greater satisfaction and engagement.

In contrast, other principles such as flexibility deal with the adaptability of the solution to various needs, robustness refers to the reliability and durability of the solution in different conditions, and contrast pertains to visual elements and differentiation between components. While these principles are important in design, they do not specifically address the navigation aspect as directly as ease of use does.