I work in the area I studied (environmental engineering) thinking I would get to be outside often, work on projects that benefit the public, work on a variety of projects, and have a profession I could be proud of. All of those things came to be.
Except I'm miserable. I don't want to work 6am-6pm 6 months a year, take 10 days of vacation a year, spend more than it costs me to live in taxes every week, while supporting the girl who's pay and prospects are even worse than mine (and I'm significantly above average for my age), until I'm 65 when I'll theoretically be able to afford to die.
As far as I see it, this is it unless I'm willing to cheat someone or unless I get lucky somehow.