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.