A user-friendly interface is very important to a knowledge worker's system because:

A user-friendly interface is crucial for a knowledge worker's system primarily because it allows easier navigation and accessibility. When a system is intuitive and straightforward to use, knowledge workers can efficiently locate and utilize the tools and information they need, which significantly enhances their productivity.

An intuitive interface minimizes the time spent managing technical complexities or learning how to use the system, thus allowing users to focus on their tasks more effectively. This is particularly important in environments where quick decision-making and access to information are critical.

While other factors, such as collaboration and data analysis capabilities, are important in a knowledge worker's environment, the core benefit of a user-friendly interface lies in its ability to streamline the user's experience, making it easier to perform various tasks without unnecessary complications.