It doesn't take much these days for a tale to be described as a "Cinderella story": anything resembling a makeover, however superficial, will usually suffice. But Breakfast at Tiffany's really is a variation on the Cinderella theme, the tale of a young girl who escapes a dangerous adolescence and transforms herself through aspiration – a sheer act of will – but who may not live happily ever after. Like Cinderella, it is a story about struggling to escape. And it is a story about self-fashioning. Breakfast at Tiffany's suggests to every woman – and many of the men – in the audience that they could reinvent themselves, liberate the golden girl hidden beneath ordinary, even debased, trappings.
Much of the writing about the film of Breakfast at Tiffany's acknowledges that when Hollywood bought the rights to the story, Capote wanted Marilyn Monroe to play Holly Golightly. Most accounts treat this as yet another of Capote's many idiosyncracies, if they consider it at all – who could imagine Monroe instead of Audrey Hepburn in one of her most iconic roles? But for anyone familiar with either Monroe or the novella, it's not really that much of a stretch.
https://www.theguardian.com/books/2009/sep/05/breakfast-at-tiffanys-audrey-hepburn