alt Hacker NewsLast time I lived in a city was a while back, but at that time Denver updated routes a few times a year. I'm not saying they are the speediest, but I don't know how you are claiming that no new route can be created in any Western city without years of work. That simply is not true.
Or, if you want to go small, my school district changed bus routes with a 48 hour turn around time when we moved to our home in the country, and again when our teenager's schedule changed and he could no longer drive the younger sibling home.
Routes should not be created or changed often. People need to rely on transit, if they can't be sure their route will still be there for long they should buy/drive a car even if there is good transit today since they will need that car when the routes change to something that doesn't work.
changing routes is needed of course. Cities chanre and you need to follow that. They don't change fast though. long term routes also drive change as people adqust their life to what they can do.