Originally Posted by
stut
The usual reasoning given for the time it takes to replace the escalators on the Tube is the age of the system - unusual, cramped tunnels and odd sizes mean that most of the escalators on the system can only be custom-built on site (in very difficult conditions).
Have you noticed how long the (up?) escalator in Bank, from Northern Line to DLR (and Circle/District via Monument) has been out of action? It feels like it's been out of action for a year, and during that time I've frequently used the escalator directly beside it and never hear nor see anyone working in the area. Maybe they truly have run out of money, or can't afford to pay people to work 24/7 (or close enough) to get it upgraded. It's also a relatively modern area within Bank (linking the DLR, which has only been around since the late 80s).
I was also suprised how long it took the escalators in Canary Wharf to be torn down and reconstructed in the opposite direction, a couple of weeks. Obviously a lot cheaper for them to take their time and snarl up the pedestrian flow than just get it over and done with.