I adore the London Underground, it's my absolute favorite subway, of those I've been on. But of course, I'm a tourist. If you take it every day, it becomes routine transportation, and you might be frustrated enough with it to write a hilarious song like this.
Warning: loads o' swearing, if you're sensitive to that kind of thing. I personally cracked up every single time I watched this. Oh, I gotta go watch it again.