It's better to learn them before you break them. For many of you, practicing law is your first real, professional job. This presents the double challenge of both learning how to practice law and learning how to function in a professional environment. It's not that if you break these rules there will be specific sanctions, but rather if you follow them your professional life will progress more smoothly. These rules run the gamut from understanding who's who in the firm's pecking order, to whether you can turn down work assignments, to how a particular partner prefers work to be presented.
Some rules are more important than others.
You learn them by watching the partners and associates who've been around a while. Partners often comment on clothing choices by young associates and do not like to have to tell them that their choices need work. You'll avoid some unnecessary headaches if you find out through observation what some of the rules are, and follow them as best as you can. Your intelligence and knowledge is not all that matters. Up to now, you have succeeded in what you have set out to do primarily because of your intelligence, your discipline and your ability to persevere.