A Door Leading to Mid-Air

I have to assume that when this was built it had a balcony on the second floor. The balcony is long gone, but the double door remains. It seems a little odd to me that it has a dead bolt above the door handle. Were they worried someone would climb up to the balcony and enter the building that way?

For the All New Scavenger Hunt #6 - A door no longer in use.

Done