On a suggestion from my unwitting mentor, I picked up and read this book, The Design of Everyday Things, by Donald A. Norman
This is a fantastic book which I recommend to anyone. Norman approaches this book from the perspective of both a frustrated consumer and a researched academic/industry professional, attempting to categorize and quantify the components that most strongly contribute to high usability.
Norman analyzes many things which are encountered daily but taken for granted -- a common example is the shape and appearance of door handles, which he uses to illustrate a number of his design principles. One of these is affordances, a concept I first discovered here. Affordances are qualities of objects which indicate how they are to be used: for example, a flat panel affords pushing, whereas a handle designed for gripping affords turning and pulling. A flat handle on the pulling side of a door is an endless source of frustration for many simply because the shape of the handle indicates the wrong action. Readers might note that fire doors always are pushed to exit, and not only is the exit panel flat to afford panicked pushing but that the handle also has features to indicate which side of the door the hinges are on. These affordances are mandated by law.
Another topic on which Norman spends a great deal of time is the concept of errors. Most users will conclude that if they are unable to use an item properly, it's their fault. Norman maintains this is really the designer's fault. Errors are a natural part of use even in a well designed object, and thus errors should be difficult to commit by design, or they should be easily correctable if at all possible. An example of an error which is hard or impossible to make (referred to as a 'lockout') is the barriers placed in large building staircases between above ground and basement floors: they prevent panicked people from continuing to run down stairs past the exit level. Like the fire door handles, these are also mandated by law. The gold standard for errors that are easy to undo are anything that can be reversed with 'ctrl-Z'. Indeed so many programs have this and it is used so frequently that many of the artists I work with will instinctively reach for these keys even if they're painting with oil and canvas! Therefore it's not only a good example of easy to correct errors, but also of standardization.
These are just a small sample of the wealth of information contained in The Design of Everyday Things. Overall Norman emphasizes simplicity, usability, readability, the utilization of natural human motions and intuition, and a host of other robust principles as foundation for design. This book will give you an appreciation for design you have never noticed before -- from knife handle shapes to the layout of a Chipotle -- as well as allowing you to quantify why you can never figure out which light switch does what in your living room. Thorough recommendation!
Design of Everyday Things on Amazon