Reconciliation?

For many, cheating means the absolute end of a relationship. For others, reconciliation is the goal. I haven't been in that position, so my thoughts are based on naïveté and guesswork. When a friend's spouse cheated on him and he was trying to decide what to do I asked him, "Was what you had before this incident something worth fighting for?" To me that seemed like an important factor in his decision on how to respond. I would really like to hear from those with experience as to whether that makes sense or not.