My "new hire" treatment as government contractor was so bad I almost quit. Even though it's a huge organization there's no process at all in place; you're just thrown to the wolves. Basic things like where and how to get my security badge and car tags were not covered. I was not given any input about what was expected of me, but I found out about things I was supposed to do only when I was getting yelled at for not having them done. Everyone I work with are of the baby boomer generation, while I am a millennial, and instead of mentoring me they excluded me. Often I would get in trouble for missing meetings because the location of the meeting was spread by word of mouth but no one would come by and tell me. My first project was to port some code written by a much older engineer, but this engineer believed that he had job security if he were the only one who knew the system. Our boss told him "You WILL let him shadow you and read your code," and he shot back, "He will NOT shadow me and he will not see my code!" For the first few weeks, the only copy I had of the code I was supposed to port, I got from snooping in his trash when he threw away a CD (old hacker trick :) ).
Things got better eventually but it was definitely the worst way to treat a new hire.
Huh. I had a government job in highschool; I went to a poor school with a big 'occupational program' where you get one or two periods off and some school credit to go to work, you know, to help the kids who are thinking of dropping out get a diploma. It was pretty sad because there were mandatory class days where they showed you videos about how to be a better retail employee; I can still tell you the steps they taught us to spot short-change scams and shoplifters. It's sad because they could have just as easily spent some time talking about various trades one could learn by becoming an apprentice. I had a job at the local computer repair shop the summer before[1] where I obtained some contacts, so I became the IT guy for the local county health department.
It was a really great experience for me. I was about 16, and I think 40 was pretty young for the office. I don't know if I got much by way of mentoring as an IT guy (well, later on they hired another guy who was way better than I was and I did get some mentoring, but for most of the time I was there it was me and the office manager, who probably knew less than I did about most computer things) but there was a lot of /very important/ social mentoring I got. I learned how to (at least kind of) act like an adult, or at least how to interact with adults in a healthy manner. On a social level, the semi-technical guy who hired me was one of the best people managers I've worked for.
I think it was an all around win/win; I got treated like a human being (which feels /incredibly special/ to a high school kid.) and I learned how to more productively deal with less-technical adults, and I got out of some school. They got a reasonably skilled IT monkey for minimum wage.
After I got out of high school, of course, it was .com time, and I have not had reason to look back at government work since, just because I don't value stability that much and there's little chance I'd have the patience to wait it out long enough to get the pension. I still look back somewhat fondly on my time working for the state. (Or rather, the county.)
[1] my stepmother made me quit that job 'cause they had no workman's comp and I was being "exploited" for slightly under minimum wage. I was 15! it was far less dangerous than anything else a kid that age might reasonably do for fun, and they gave me discounts on used computer parts for the next three years, so I thought it was great. Anyhow, it worked out okay, but it's another side to "exploitation"
Contractors are the lowest scum in the pond in the Government (they all know your making twice what they do). "Real Employees" get treated a little better, but you'll often find the same indifference.
I work in a French administration. We have a special day, the "journée des nouveaux arrivants" ("newcomers' day") for new hires, where we are taught the history of the service and learn about the different departments. The only problem is, since there are few new hires and organizing it requires the animators to be here, that this event takes place about twice a year.
I was lucky, my manager thought about it and managed to get me to do it after a bit less than a year. Some people have been working here for years without the "new hire day" (in all fairness you don't learn a lot of practical things, but still...).
I did some work for the government while in college. While I'm glad I did it, as it gave me a purpose and venue for my essentially self-taught advanced coding, I would never do it again.
I did work for the city gov't too while in college. It was a strange experience, being the only computer intern working for the Dept. of Agriculture, giving my end-of-summer presentation about JS and Access forms to a room full of other students who spent the summer hiking around farm fields taking measurements.
Things got better eventually but it was definitely the worst way to treat a new hire.