Western New York, nearly every house has these doors, they are usually located at the back of the house and some of them are pretty Fancy.
Was it a feature for some sort of technology no longer used?
In Europe I have seen similar set ups with usually a winch wheel at the top. They were basically used to lift heavy stuff up to the second floor. Often in merchant shops where they needed to get barrels of goods up to the second floor for storage.
Especially outside of "converted" warehouses/factories now fancy lofts, they were likely used to winch up goods up to top levels of the building. If not, it may be an old fire escape door that no longer has stairs leading up to it. Or a balcony used to be there. If you're curious, take a closer look around the window to see any signs of removed equipment. Unless the building has been refinished, you may be able to see marks from where a fire escape, balcony, or winch above the doorway would have been.