There are some individuals that actively seek out trouble. This is likely due to a combination of bad personality and no proper outlet for their stress. They want to feel powerful and physically superior to other men. Eventually, there is a day where they tell themselves that they are going to do it.
They will pick a target they think they can take on and attempt to start an altercation with them. Many of these things happen when the aggressor is intoxicated, but there is a special set of people who do it while seemingly sober. These individuals are essentially bullies, though the target they attempt to pick will look only a little bit below their league in terms of physicality, but not a massive difference so they don’t look bad.