I generally like SFO. As far as airports go, it is clean and well-lit, the signage useful, the staff largely competent. It also sports a CLEAR lane, meaning I can whiz through security in seconds rather than minutes, and there is even a yoga/meditation room for pre-flight stretching and relaxation.
The airport designers have surely put not a small amount of thought into getting people to move efficiently through the airport space, from the public transportation through the terminals, the parking lots, and even the shopping.
However, SFO fails utterly in one very simple and specific place: the restrooms.
The facilities extend forward away from the entrance, and are split in half length-wise. One the left side, the toilet stalls and urinals, on the right, sinks and space. They are separated by an impassable wall, so that moving from one side to the other requires a trip around the near or far end.
It's actually an excellent system; go left and forwards to hit the toilets or urinals, keep going forwards and turn right, coming back towards the entrance to wash and dry hands, maybe re-arrange luggage and change clothes, then exit out of the single large, doorless entrance/exit.
To guide traffic, there is a wall immediately inside the doorway, effectively a pedestrian round-about. So coming in, immediately go left, do your business, loop around, wash your hands, and come out the right side; no awkward shoulder bumps or traffic jams.
The huge unmistakable arrow directing traffic immediately upon entering points right.
This flows traffic into the sink area, whereupon everyone who actually wants to use the toilets or urinal (basically; everyone?) now has two choices:
1. cross to the left, cutting straight across the flow of people coming out after washing their hands, or
2. go deep and loop around counter-clockwise, walking completely against the flow of people who are coming clockwise to wash their hands after doing their thing.
What, in the name of all that is righteous and true in the world, is the point of designing such a simple and effective bathroom layout, only to send people into it THE WRONG WAY?!
Does SFO expect that most people entering the facilities actually want to wash their hands and perhaps change their clothing BEFORE using the urinal? Is that the predominant use-case for which designers and architects planned?
And I tell you, there is some deep and powerful psychology at work; we obey arrows. We must.
I have gone through SFO at least 20 times in the past nine months, I KNOW on which side the urinals are located. I KNOW the flow of people is counter-clockwise. And yet I STILL obey the arrow, bump into someone on his way out, then cross left and dance with some guy and his rolling luggage confused as to where he can pee before changing his shirt.
So close SFO, so close. And yet: utter fail.