I will answer this like it was a real question.

People in general who are not criminals think too much if they find themselves in trouble. They know something is not right then they hesitate instead of attacking. You let someone hit you first your fucked.

They wait until it's too late to do anything to save themselves because they think too much.

If they see something wrong it is wrong. Instead of letting it play out. Make up your mind to do something. Don't worry about what could happen to you if your wrong like being arrested. Instead worry about what could happen to you if your right.

You can retreat however you never want someone you don't know to get into your safer space. Extend your arms out in front of you. Anyone tries to get into that space you hit. In the throat, eyes, balls and don't stop until he is down and then get the fuck out of there