Doors and idiot-proof design

I don't know how to use doors. Not even the ones with instructions written on them. If they say "push" I pull, and if they say "pull" I push. I've been locked in, locked out and locked between doors. I can't easily find the handle to get out of my own car. Let's better not talk about keys and locks...
I'm not being particularly smart here, but it seems that the error is more common than I thought. And it seems that my stupidity is not the only cause.

"Somehow, when a device as simple as a door has to come with an instruction manual — even a one-word manual — then it is a failure, poorly designed."

That's a phrase from Donald Norman's book, The Design of Everyday Things. Donal Norman is a cognitive scientist that works on Human Centered Design. That is inclusive and error-proof design that places usability before appearance.
I do like him. Now it seems that I am at least as idiot as the designer of the door.
He continues to explain how we use doors:

"When we approach a door, we have to find both the side that opens and the part to be manipulated. [...] We expect to find some visible signal for the correct operation: a plate, an extension, a hollow, an identation - something that allows the hand to touch, grasp, turn or fit into. This tells us where to act. The next step is to figure out how: we must determine what operations are permitted, in part using the affordances, in part guided by constraints."

For me it is really annoying when I approach to a double door and I take my time to analyze it. I see the plate. I see that despite of being a plate that looks so "pushable" I'm supposed to pull it. I find the right place to pull. And finally I get to the door and pull it with enthusiasm only to find that it won't work. I push and nothing happens. I pull again and start to get nervous, to fell ashamed, to get irritated... I try to convince the door to open itself, until I realize that this door is locked. I was supposed to pull the door next to it. Of course, there was no visual clue making it clear where to pull.
Poorly designed doors affords a large range of actions, and they don't constraint those actions.
Constraints are the properties of objects that limit what can be done with them. Constraints can be physical, semantic, cultural or logical.
Affordances are the possible uses, actions and functions of the objects perceived by the user.
While "affordances suggest the range of possibilities, constraints limit the number of alternatives".
When properly used on a design, the combination of affordances and constraints make the object easy to use because it is clear how to operate it.
For doors, designers can start by using different hardware for pushing and pulling. If the door looks the same on both sides, then it's obvious that's going to be confusion. Use plates to indicate pushing and horizontal levers to pull, it shouldn't be that hard.
If you can't do that because the door would be less appealing, then please leave it open so everybody can get in and get out without trouble. After all, "if an error is possible, someone [like me] will make it".
Here are some amusing stories told by D. N.:

• Someone couldn't get off of the Paris Métro because the doors didn't open automatically, as they do on most subway trains. He just waited patiently, but the train started moving again.
• Somebody fell to the floor while trying to push a door that opened inwards automatically.
• Some robbers couldn't open the doors into the restaurant they planned to rob. They pushed, pulled, (and kicked), but they were sliding doors. [1]
• Sombody got trapped between two rows of glass doors because he got distracted and moved a little to the side and tried to open the door pushing the glass supporting pillar.

I'm not feeling lonely anymore :)
Luckily I have a lovely family that's used to help me in this situations. I hope they do too. If not, we can make a support group (but not in facebook, please).