The phrase "be off target" can be replaced with various synonyms, such as "miss the mark," "fall short," or "go astray." These expressions all indicate that something or someone has failed to achieve a goal or objective. Another option would be to use "misguided," which suggests that the person or object was headed in the wrong direction from the start. Similarly, "errant" can be used to describe something that has strayed from its intended course. No matter the phrasing, the common thread is that the subject at hand did not hit its intended target or failed to accomplish its intended purpose.