The doors are timed, via a wireless signal from each button. The first door you you go through from either direction will open automatically, and a wireless signal will activate the second door to open after the first one closes behind you.
The purpose of this is to save energy and reduce the intrusion of bad weather, rain, leaves and the like from blowing into the lobby. And from many accounts, as well as our own observations, it is already accomplishing this task handsomely.
This does delay your coming and going, we realize. And, it is possible the signal from one button to the other could be blocked from time to time due to a number of variables. If for some reason the second door does not open for you, the inner buttons will open the doors as well. They are set to a delay that matches the timing of the doors closing. The button on the brick wall, will activate the inner lobby door, and the one on the frame of the northernmost door, activates the door going out to the plaza.
If you have any questions or concerns, feel free to contact the office.