I learned Ada because I took a new job back in 2008 (at Boeing, doing spacecraft modeling and simulation) and discovered on my first day that I would be using Ada. Naturally, I was expected to just pick it up on my own (Not complaining, that's pretty much how it goes these days).

My mother (who found it amusing I was going to be coding Ada in 2008) gave me her old Ada books from the 80s (her employer at the time sent her to an actual course to learn the new DoD mandated language, back in the days when employers invested in their people), which I still have. I ended up programming in Ada up until 2012, when I managed to get a job using Java.

The language itself I rather liked (better than Java, for sure). It's the only language I've ever used that tended to produce programs that worked correctly on their first run (getting them to compile was the difficult part). The aerospace industry OTOH, I don't miss.