I believe somewhere I came across a book (possibly Stewart Brand's How Buildings Learn, but I might be completely misremembering) that claimed that people in wheelchairs generally would prefer ramps to elevators.
Meanwhile, the MBTA's major project to retrofit accessibility into stations seems to be 100% focused on elevators, which sometimes break. I'm sure there are some stations where installing ramps would be difficult, but I think some ramps would have been possible in some places, and as far as I know no effort has been made to install any ramps.
There are several people who contribute to this site who aren't able to use stairs or escalators, and I'm curious to hear their views on this subject.
I think trying to generalize in this respect is just wrong. Elevators break down, unlike ramps, but it is possible through preventive maintenance and supervision (so they don't become toilets) to minimize the downtime. Also, a larger institution would have multiple elevators. OTOH, ramps can be difficult or easy depending on design, length, width, and steepness. An ADA-qualified ramp is steep, 1 inch rise per foot run ... put that in a percentage and think about the signs that would be warning trucks on a downgrade on a mountain freeway. Also consider the space this takes up, 36 feet to get up a 3 foot porch (not counting flat spots now and then for resting or turns). Some AU people who watched me go down the ramps at LAUS were probably appalled at my unsafe speeds and happy they were out of my way. However, the method I use is really the safest way to keep control because if (when) I lose it (all it takes is a slick spot on the floor, or an uneven spot that leaves a drive wheel off the ground with no traction), I run highspeed into the side and stop or capsize.
You are also going to have differences depending on manual or power chair, or scooter. (Scooters are not as maneuverable, especially the larger outdoor ones, and can have trouble with switchbacks.)
There is an interesting spot where I take my mother to Kaiser appointments. It has an elevator and a ramp with switchbacks that go the same place. I use a manual chair and prefer the elevator up, except when it has a line and the ramp is faster. My mother, as she ages, has gone from ambulatory up the steps, to walker up the ramp, to walker in the elevator, to scooter up the ramp, to manual wheelchair with me pushing (a good trick, definitely elevator, or get help from someone up ramp when elevator is out).
There is another design issue besides elevator vs ramp, and I suspect the answer from PWDs would be more consistent than your question. I prefer integrated adaptations. In other words, I don't like when the elevator or ramp separates me considerably from travel companions. I would like to be able to continue a conversation as we each take our route, or be apart a short enough time that I don't miss too much, and I prefer that their route and my route begin and end at the same place. I also don't like adaptations that are a lot of extra distance, or that require help to find; I do enjoy the detours involving freight elevators because I enjoy behind-the-scenes tours, but that is not appropriate in new construction.
