Good design is also an act of communication between the designer and the user, except that all the communication has to come about by the appearance of the device itself. The device must explain itself. The Design of Everyday Things (1988)
In their work, designers often become expert with the device they are designing. Users are often expert at the task they are trying to perform with the device. [...] Professional designers are usually aware of the pitfalls. But most design is not done by professional designers, it is done by engineers, programmers, and managers. The Design of Everyday Things (1988)