The former UK prime minister Margaret Thatcher famously changed her Lincolnshire accent to come across as higher class. I have friends who moved to the big city to pursue their careers and consciously changed their accents as well so that they would not be discriminated against. I did the same, while living in Germany and the US - I always focused on getting the accent and idioms right, instead of the grammar, because I knew that sounding "like them" would increase my chances of being accepted.