The phrase "fails to honor" is often used to describe situations where someone doesn't keep their word or live up to their responsibilities. However, there are many synonyms that can be used to convey the same idea. For instance, someone who fails to honor their commitments can also be described as unreliable, untrustworthy, or deceitful. They may be considered disrespectful or dishonorable, and their actions could be seen as a breach of contract or a violation of a code of ethics. Other synonyms for "fails to honor" might include neglect, ignore, or disregard. Ultimately, the choice of synonym will depend on the specific context and the desired tone or emphasis of the message.