William is trying to explain a principle of layout and interface design guidelines to his colleague.
Explanation:
The principles of user interface design are clarity, interfaces, conserve attention, keep users in control and direct manipulation.
The visibility of system status match between system and real world, user control and freedom, flexibility are some guidelines for principles of user interface design.
Principles of design work together to create something that is pleasing and optimizes user interface.
Click on the pic and it will pop up this is how