I never thought about it much before, but I realized after seeing window cleaners hang upside down and floating about like rock-climbers under the new bubble for Triangeln train station in Malmö, that it is a very dangerous job, and needs a great amount of skill to pull of smoothly and hopefully survive without falling on your face.
They get extra hero points for looking cool too.
Architectural styles change, accordingly changes also the way it is handled, used and maintained. New ideas create new engineering techniques, new materials creates new industrial techniques.
But what strikes me the most right now, is that new architecture creates new cleaning techniques. Who would have thunk? (You can mentally insert a smiley face here if you want, I won't type it)