But: The one big question I have with elevator UX is this: why isn’t it possible to deselect a choice? So pressed 10th floor but wanted 11th. There is no way to press button 10 and then button 11 to correct that mistake.
Will I ever solve this mystery?
To deselect the floor, simply press in again.
My local pizza place plays music based on customer voting through a smartphone app. It's not necessary to be there in order to vote - you just need the app.
This elevator design could be fun in similar ways.
1. When the currently targeted floor is deselected and the remaining selected floors are all in the other direction: Then the elevator would have to either reverse course without stopping — a situation which otherwise doesn’t occur and would be unexpected and possibly dangerous for the passengers — or stop on a non-selected floor before changing direction, which would be confusing as well.
2. The deselected floor was the only selected floor: The elevator would then have to choose a floor to stop on by itself — e.g. the next one it can safely stop on — which is also a situation that doesn’t otherwise occur. In addition, deselecting the only selected floor doesn’t seem to be a practical use case.
So instead of having to define, implement and test a behavior for those odd situations, it’s safer and less costly to just disallow deselection.
(I don't usually board elevators traveling in the wrong direction, ofc., so, I'm not that sure.)
HN is not representative of the average person, or even a standard cross section of society. A elevator has to be legible to an 8 year old child, an 80 year old retiree, someone who is blind, a person who is deaf, etc.
When designing for such a broad audience, KISS (keep it simple, stupid)
[1] https://www.amazon.com/Qualityland-Visit-Tomorrow-Marc-Uwe-K...
Now that you can unselect floors, if the elevator is on its way to the 5th floor and you unselect it, should it skip that floor mid-movement?
If there's only one floor selected, we'll probably want to disallow unselecting it while the elevator is moving, but what if you just hopped on and it hasn't moved yet?
This would probably make for an interesting interview question.
But yeah, I'm sure that at all of the various elevator companies, over all of the years that elevators have had electronic controls, nobody has bothered to put any thought into this.
In these cases, it is simply the best UX to keep everything really simple.
Until someone punches you out, of course, because it'd be hard to hide and you're in a confined space with them...
If you can go back and forth, it would probably get violent.
Admittedly, that's not very helpful unless you somehow knew that the elevator you were in had been configured in such a way.
In many elevators, one can double-press a button to deselect it.
You are perhaps trying to optimise for a one-person elevator trip, rather than thinking of what is the optimum for a repeated game with many concurrent trip players that includes both cooperator players and defector players. An elevator is a common good to its users.
If people could cancel a destination, then there is less incentive for people to have to prethink their destination before getting on the elevator. Leading to more likely to waste concurrent elevator users’ time in the long run?
If you could cancel a destination, defector players could cancel your destination to speed up their trip (with resulting policing and status meta-games etcetera).
Elevators mostly have the lowest-common-denominator for a UI. Where is the incentive for elevator purchasers (building procurement or facilities) to demand an improved UI? Would a manufacturer get any profit by providing an improved UI? Would such a UI be accessible to the blind? Discoverable? Usable? Cleanable? Predictable (e.g. elevator arriving indicators on destination floors)? Safety? Complexity?
There are a huge number of factors to building anything complicated.
Also see https://danluu.com/sounds-easy/ and https://fs.blog/chestertons-fence/ and all of the elevator wiki starting here https://elevation.fandom.com/wiki/Fire_service_mode_(EFS)
Disclaimer: I’m not an elevator engineer. I feel your pain: I want a government department of niggles which catalogues minor complaints and gets them fixed. Although I admit I am pessimistic enough to think it would only end up increasing the total number of niggles due to second-order effects.
You'd be surprised how often it comes in handy and have never had an issue with anyone deselecting someone else's floor.
In larger/public settings, offering this would be counterproductive, for the reasons listed by sibling comments.
And maybe answer my question too: how do blind people know if they are selecting or deselecting?
Watching foreign button-mashers must be amusing!