I saw a video where the question was asked if they had the ability to know when a man is cheating. They all said they did. The interviewer then asked them if they knew when a man cheats, then why do they not know when he’s unhappy. None of them could answer.
Some men cheat because they are cheaters.
Some guys who cheat are doing it because they want to, not because they are unhappy. Some are accustomed to variety.