I once worked as a telemarketer (as if the job itself isn't a big enough lie.
Anyway, at the time I was going through a bit of an identity crisis and had a very bad habit of speaking in a british accent in public. I don't know why I did it, I just did, and it was one of the stupidest things ever. I don't know if my accent sounded genuine but if it didn't I can imagine it made me look like a huge idiot.
Anyway, I went to the job interview talking normally, but for the entire week or so I was employed there, I spoke in that british accent...to my bosses...to my co workers...and worst of all I actually had some friends who worked there who also went to my high school and knew how I really spoke...and I did get a few puzzled looks from them sometimes.
After a week at the job though I hated it. I actually hated it almost since day one because of what they were training us to do. Badger people into buying stuff...never accept no for an answer...if they begin to refuse talk faster and more forcefully. I call that harrassment and I didn't follow their code. I usually accepted "no" for an answer and didn't badger people, which didn't sit very well with the supervisor who gave me a talking to several times about how I needed to be more forceful or they'd have to let me go.
I quit. And I never looked back. And I'm still embarrassed to this day that not only did I work as a telemarketer, but I lied as well by speaking in a foreign accent.
So, there you go. Lesson learned.