Why don't elevators automatically go to the ground floor after being idle for some time?

Question

I work in a regular 10-story office building with 4 elevators. Every morning I notice a situation where all 4 elevators happily sit on one of the topmost floors until someone pushes the button from the ground floor. It seems quite inefficient to me, as 99% of the trips until 10am happen from the ground floor (or parking garage). Likewise it would be best to move the elevator to the 5th (middle) floor between 4pm and 6pm, as that's when most employees leave the building.

So the question is: why don't elevators automatically go to the ground floor if left idle? (at least during the morning).

Answer 1

Some do. I've noticed this at particular hotels and larger office buildings in big cities. It's not exactly common but it is something that some building managers set.

In general I'd assess the reasons down to two possibilities, out both:

1. Laziness
2. Lack of useful data

Reasoning for laziness is easy enough: the wait for an elevator from any floor to the bottom isn't so great that it actually is cause for concern or significant delay on average. There are always the outliers, but they're the minority.

Data is the bigger reason since most buildings don't have data analysis tools to determine where the best place for the elevator should be, be it the first floor or something else. Buildings with their own underground garages may have more traffic from there than from the ground floor. Certain floors may have more traffic to and from their floor. Without some system contently gauging this, it's impossible to tell which floor the elevator should be on to save users the most time. Furthermore, doing so would be at the cost of the building, both for the hardware and software necessary to mine and analyze the data, and for the electricity and additional maintenance cost of the elevator.

So why not just have all elevators default, say, after 10 minutes of non use to go back to ground level? Again, that's something else that would need to be maintained and handled if anything were damaged.

Ultimately the UX of elevators isn't significantly worse because of this missing feature, though with enough research you could definitely make the case that the 1-3 minute wait could be cut in half (or some figure) which, in just one building, would save some enormous anoint of time pretty year for all employees and this help generate a significant return, making it worthwhile for buildings to charge more and offer the service.

If you so and you're successful, that'd make for an amazing case study!

Answer 2

Newer elevator systems do exactly that. In fact, newer elevators change the user experience fairly dramatically by having a keypad on the ground floor where passengers enter their destination floor BEFORE boarding an elevator. The system then computes which elevator will provide the speediest service and directs the passenger to that elevator. The system can even account for multiple waiting passengers and optimize multiple elevators to provide the fastest service for everyone. See this article about such a system that was installed in the notoriously frustrating elevators in the Marriott Marquis hotel in New York City.

Answer 3

Some buildings have systems to remedy this somehow. For example, my office's building only allow one elevator at a time to go up or down if you call it from any floor, but you may have 2 or 3 elevators going the same direction if you press the button from the inside.

It solves some issues but create other issues, for example, when everybody is going home at the same time, everybody calls the elevator yet only 1 will go up (guess the system doesn't have a way to discriminate by time of the day).

However, I think the way normal elevators work is a common affordance, and as such, it should be kept.

Please note that devising a system to do what you say, even to make it waaaay more effective is quite trivial, yet not very common, even on modern elevators. And this is because it's a really unexpected behavior

For example: let's say people is moving between floors. Imagine a mail clerk, or a janitor, or security. They just left the elevator, and when they get back, it's not there anymore, even though nobody is using it. This would be really frustrating!

So, in short: elevator should be where you left it, no "ghost behaviors" needed.

Answer 4

Just my opinion but I would think there are odds that someone on the fifth floor is grateful that it didn't go down to the first floor. The odds someone on an upper floor will call for service is just as good as someone on the first, making a run to their floor faster with less wear on the elevator.