“Number of clicks to get anywhere” seems like a useful criteria. But over time you will see that what really counts is not the number of clicks it takes users to get to what they want but how hard each click is—the amount of thought required, and the amount of uncertainty about whether they’re making the right choice.
Don’t make me think
Being an expert in online usability Krug gathered his experience in a wonderful book. This summary of key thoughts will help you to remember most important principles and laws.