People can be hurt or even killed. Instead, when you go into any building, check out the exits. Note where they are, especially at least two of the ones nearest you. And if you ever notice a marked exit door blocked or locked with a chain from the inside, contact the buildings manager right away and have the door opened. If they refuse, leave and call a code enforcer or fire department immediately.
Security is no excuse for endangering lives.
They are lit by emergency power if the building's lights go out. Learn to notice them. They can be signs of life.