I enjoyed a GQ article from 2009 about the day-to-day life of an air traffic controller. It's a high-stress job that pays poorly, requires overtime, and has really shitty tech.

"These airplanes are headed toward each other on intersecting runways. Too fast. Too soon. Here it comes. The MD-80 is not over the threshold.… Fuck. “Go around!” Cali says into his headset, instructing the RJ to abort its landing. It’s too close to the MD-80. It’s too close… The plane swoops down, then up abruptly, like a gull with a fresh kill." […] "LaGuardia has thousands of go-arounds a year. At an airport like this, everything is a close call, everything is dependent on split-second decisions, snap judgments, jets constantly barreling toward each other. It’s people, just people, with nerves of steel and uncommon courage, keeping the planes from bashing into each other. Just people."

I always assumed the whole operation was mostly automated. It's terrifying to learn how manual and error-prone it all is, plus how unhappy most of the controllers are.