I just started working at a 31-story corporate office with sixteen elevators (A-H for 1-15, I-O for 15-31), and the elevators here incorporate a genius move... outside the elevator are little panels with numbers, and you choose the floor you want before you get on the elevator comes. The panel tells you which elevator you should get on. This way, the system can optimize ahead of time where the different elevators should stop. Since I've been here, I've never waited more than 15 seconds for an elevator.
Those work nicely in office buildings where people know the routine. When you put one in a hotel, you'll usually see someone paid to stand around and show guests how to call the elevator.
There is no up/down button, just a keypad with numbers on them. People are accustomed to looking for the up button and, upon not finding one, immediately get into a confused state.
If you need lengthy instructions to show someone how to use your UI, you should reconsider your UI.
At the risk of completely derailing the discussion, sometimes the UI simply just needs to be learned. People who are unfamiliar with elevators would have no idea how to use one.. there's no instructions anywhere, just a panel with numbers. If you aren't familiar with those bathroom faucets that turn on when you put your hands under them, you'll spend a few minutes just staring at it looking for a knob. Eventually, it catches on.
You are right that there's an initial curve, though, and I don't know how to deal with that other than just through the painful experience you described.
Of the top of my head: start off with big up/down buttons. Then show a list of floors. Some people won't notice the second press required, but it's a start. I was confused by those things the first time too.
People see an open elevator door, they get in the elevator. They don't stop to read the instructions because they are not expecting the elevator to come with instructions and also because they know the elevator doors are not going to remain open forever.
These people are already getting on wrong elevators. The example given has banks of elevators for different floors, marked by sign and by buttons for the specific floors covered. If they don't pay attention they'll get a short tour.
If this was a deadly choice, between an elevator and a trash compactor, it might make sense to over-sign it. As is, it's a trivial and obvious mistake, especially if each bank has a sign saying 'Floors 1-x are reached via the other elevator bank' for someone to read on their round-trip.
Part of the reason users are so clueless is because we go too far in padding their environment. People don't slice off fingers because the sharp end of the knife wasn't properly labelled - they exercise caution.
I saw this implemented at (I think) Times Square Tower a few years back. It had you enter your floor at a podium in the main lobby on the way to the elevators, and it worked beautifully. 49 floors and not once did I have to wait more than ten or 15 seconds for an elevator.
Then they retrofitted a similar system back at my corp HQ. It had you enter your floor on a screen on the wall right in the middle of the elevator lobby and it was (and is) kind of a pain in the ass...because when there's a crush of people waiting for the elevators, you can't get to the screen to enter your floor. When it was just the "up" and "down" buttons in the same location, the odds were pretty good that someone in the crush had already pushed the button you need, but...
That's a good idea. Having that, plus an 'expected wait time' would be really useful. When I push the button, if it tells me I'll need to wait for 4 minutes and 23 seconds for the next elevator, I can use that time more effectively ... maybe go grab a coffee and come back, or perhaps even take the stairs instead.
I don't think owners of office buildings realize how painful it is to have slow elevators. We moved our office out of a 30 story building with 4 elevators, because the unbearable wait to get in and out of the building during peak times.
