Until I broke my ankle in a bicycle accident last year. Then I became acutely aware of how poor some of the infrastructure is around me. The closest subway station to me doesn't have an elevator, for example, and the one nearest work only has a single elevator at one end of the platform that is often out of service. I supported accessibility standards in theory before this, but now that I've seen how they play out in practice, I strongly and emphatically support them. Empathy is hugely important.
I am also so goddamn thankful that there is the requirement to have sturdy handrails alongside all flights of stairs, and that this requirement is strictly enforced (thank the ADA or building codes or whatever is responsible). With these handrails, an otherwise able-bodied person on crutches can handle staircases relatively easily. Without them, stairs are death traps, especially going down. I would have been mostly confined to my apartment without the existence of these handrails. Fortunately, they exist everywhere, so I was able to tackle the stairs at my apartment, at the subway station, at work, and in the entrances to buses.
Another "temporary disability" that most people don't think of is carrying a baby. Suddenly, doors that can be operated one-handed (or even better, hands-free) are wonderful when you're trying to get your kid someplace where you can change that blow-out.
He had no idea how to check which stations were handicap-accessible and which weren't, and when we showed him, it turns out he would have to go halfway further into Brooklyn, then get on a bus just to undo the journey above-ground. At something like 1 or 2am, too.
He just sort of deflated when he realized the journey ahead of him, so we just offered to lug him up the stairs, and did. Good thing he wasn't there alone.
It's not 'empathy' if you don't notice it until it affects you personally, or you're only doing something because it might affect you in the future.
Being affected personally at one time can (and, I assume, often does) help one develop empathy, though.
This is something that bears repeating. Accessibility means making things accessible for everyone, not just people with disabilities. It's much easier to push a heavy dolly up a ramp, than it is to pull it up lips, steps, etc. Self opening doors are a god send when carrying packages.