Perhaps someone who has managed a retail business can explain why it is so common to see a pair of entry doors side-by-side, with only one of the doors unlocked and operating.
When I see a business with 6 entry doors and only one pair operating, I feel a moment of sympathy. I say "Those poor guys. They must have expected crowds of people to show up and now they've had to face reality." However it irks me to see half of a pair of doors not working. Often a pair of doors is marked as "Exit" and I wonder if it is illegal to have one of them locked during business hours. Sometimes businesses leave half of a pair of doors locked and they don't even put a "Use other door" sign on it. It's as if customers are supposed to take it for granted that only one door in a pair of doors will work. (And I suppose that's a realistic expectation.)