The means of entering information or commands should be compatible with user skills, permitting simple step-by-step actions by beginners, but permitting more complex entries by experienced users.
Additional Information:
Most systems will have users with varying levels of experience. Any particular user may become more expert with increasing experience, or perhaps less expert after a long period of disuse. Accommodating users of varying expertise requires a mixture of different dialogue types, with some means for smooth transition from one mode of dialogue to another. For instance, as users come to learn menu codes, they might be allowed to enter those codes without necessarily displaying a menu, i.e., those codes might also serve as commands.