You can see several cases where users go astray but manage to get back on track almost immediately without any help. Since everyone who has the problem notices that they’re no longer headed in the right direction, and they manage to recover without help, and it doesn’t seem to faze them, you can ignore the problem.
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.