They deal with quarantines and bomb scares
You’ve heard these announcements -- and you probably never consider what’s actually going on, other than the fact that you’re going to be late for work. Operators have to take action when responding to sick passengers -- who are often passed out or post-vomiting or bleeding -- by quarantining the specific car and coordinating with EMTs and verifying that the right people are showing up for the right emergency. If it is a police situation, usually it’s the operator who has to work directly with police before a train can leave.
They have to act fast, even when they have little control
Train driving is mentally taxing, not just for the reasons stated above, but also because in so many situations there is so little they can do. They don’t always choose their speed -- like crawling between stations -- and so many things happen because of scheduling issues -- like suddenly going express. An operator’s worst nightmare is when someone jumps or is pushed in front of a train. Usually braking won’t stop the impact, and trains can only go straight, so they often are not able to do anything.
Emergency stops involve hundreds of people's lives and dark tunnels
When a train “goes into emergency” -- or when the train’s emergency brakes are engaged and the train stops -- subway operators are subject to the elements. The train may have stopped in a tunnel where the edges are narrow and only a few inches away from the third rail, there might be loose track to negotiate, or the operator may have hit a patch of garbage -- or something worse. Rats are known for being friendly, right? The operator has to go through a series of checks before the train can be released and put back into action. Dispatch is simultaneously trying to get them to hustle to minimize delays. Walking around the dark, varied terrain of the subway tunnels is a regular hazard for subway operators. If a subway needs to be evacuated, they’re the ones leading the way out of trains and through the tunnels, but since they’re the captains of the ship, they’re also the last ones out.