Well, you/one personally really can't worry about the structural safety of all buildings and infrastructure you're exposed to. You simply don't have knowledge,

Well, you/one personally really can't worry about the structural safety of all buildings and infrastructure you're exposed to. You simply don't have knowledge, permission or time. That's why we need the system to take care of this and prevent such accidents from happening, as well as imposing general emergency safety in case of fire etc.. Otherwise, our current life would simply be impossible.