Well, she was certainly shrewd, and knew how to perfect that
I'm-just-an-unpretentious-country-girl persona that a lot of them attempt but Dolly took to the nth degree... Was it affected and put on? Even Dolly sometimes admitted that aspects of it were indeed -- and even conceded that when she was in school she was always nice to people so, if she were to become famous, no one from her past could have anything negative to say about her.
So having a sense of humor about herself, one that seemed to be more-or-less sincere, was the trick. It's about perspective, I guess, and Dolly had it. And she knew how to corral whatever talents she had and make the best of it all. Which indeed she did. Her rags-to-riches story, though a cliche in show business -- especially in country music -- never really got old when it came from Dolly Parton because it never really felt like she was pimping the tale, even when she was.
And it didn't hurt that, below the make-up and wigs and outrageous outfits and occasional weight issues, she was gorgeous.
In other words: it worked. And when a star can make their fans, let alone the public at large, feel like her story is
your story -- at least in some vague, peripheral way -- and you've got the skill to back that up with the creative work, you've conquered the world.