Communicating on the internet is one thing, speaking for myself in an interview is another. I've improved significantly since I was a child, but I still have serious issues when interacting with others. Even with friends, in an unfamiliar and/or uncomfortable situation I can shut down.
Put me in a room with complete strangers asking me all manner of unconventional questions...at best I can't seem to make a good impression. For the questions I do understand I'll repeat the answers I have practiced like a machine, anything else and I get stuck. You ask me something I'm not prepared for and I might not even be able to complete the interview.
I've taken classes, practiced interviews with others, written reports on the proper methods for success...but it's still a struggle. These issues persist in the work environment as well, so it limits the jobs and positions I am fit for. When I'm competing for a high paying position, I don't compare well with the normal professionals.
That leaves the lower paying menial labor jobs, and even when I can get hired I seem to get taken advantage of. I have a very hard time speaking up for myself. I'm sure I could find another $10/hr job digging ditches or whatnot, but that pay level still doesn't move me out of poverty. I'm happier to be "retired" at the federal minimum wage (~$7.50/hr).
I could be better off in a lower cost of living area. I tell myself all the time I should move, but that's a far more daunting task than a job interview. Most of my family is here, but they are starting to move off. Perhaps when they all go I will too.