Give examples of how individuals can act as vulnerabilities, defenses, or threats to an information system

An example of how individuals can act as vulnerabilities, defense or threats to an information system is this given scenario:

A person can be vulnerable when someone had stolen something from him or her and she or he can’t do anything about it because he or she can’t catch the guy alone because he is armed, the police who had saw the scenario had brought a gun with him for defense and started to chase the guy and he will be considered as the defense. The threat will be the burglar as if he wasn’t able to be caught, he could be a threat towards others if he tries to do it again.