Seems like there is that little something that isn't thought about until it's happening, and there isn't a really good solution for doing it how you want it.
I had a client change the location of the dryer on a job after everything was just about done. It went from being on an exterior wall, to being against the back porch wall. I had to run the vent through the porch to get it to go outside. The wife loved the new location, the husband never stopped blaming me for not figuring out a better way to run the vent line so he wouldn't see it. In the end, I painted it to blend in and she put some furniture to hide it, so he sort of calmed down about it, but I know it will always bother him.