Over the decades, you got various companies involved in making escalators and you've got Metro varying between internal repair crews and contractors. They're dealing with old equipment, which of course is prone to break down, and the repair crews don't even know what's busted or who made the busted parts till they tear the things open. Then sometimes they have to go back to the shop and manufacture parts, because the original maker has gone out of business.

That's the original problem from which the escalator mess stems. There's just too many of them.

Metro, built in the late 20th century, is the most escalator-dependent system in the world.

It would be helpful to be able to see the layout and for the maps to label what exits to use to get to nearby sites/buildings so you aren't wandering the station trying to read the signs in the crowds.

SafeTrack - I keep saying this - is not going to fix Metro. It's a speeded up track work program, compressing three years of already planned work on the track bed into about a year.

When different generations of cars are combined into one train, it messes with the loudspeaker system.

As our eyes age, they have a tougher and tougher time adjusting to rapid changes in lighting, and we need to be aware of this.