The term 'fail to follow' can be summarized by three crossword solutions: REVOKE (6 letters), DISOBEY (7 letters), and DEFY (4 letters). REVOKE means to take back or cancel a decision or agreement, while DISOBEY means to not comply with an order or rule. DEFY is similar to DISOBEY, but it implies a more deliberate and intentional act of disobedience. All three words refer to the idea of not following something that has been established or agreed upon.