Fire EXIT?

What is the purpose of fire exit? To let people get out when there is fire? To let fireman in when there is fire?

What ever purpose it serves, it surely isn't for locking people in/out right. To my amazement, there is one particular mall who has their fire exit to do just that, lock people inside from going out and vice versa. I wonder what will happen when there actually is a fire? Do they expect their staff to go open it for the people? Who is in charge of opening it? How many people will open it during the dire times of emergency? How many fire exits must be opened? What will happen if the person in charge is on leave?

Fire exit are meant to be closed at all times and open during emergencies, it should be closed! NOT LOCK!