Why is there security in Zhao's office building at night?

Does the subject want to ask, "Why do office buildings need night security?" Protect the interests of the unit. Office buildings belong to public places. In order to protect the property safety of the office building, prevent the occurrence of fire and other emergencies, and protect the interests of all units in the office building, night security must be set up to better prevent and stop the occurrence of emergencies, which is clearly stipulated.