“When I heard they were interested in making it, I said to my agent, ‘You have to get me a meeting because I have to make this movie,'” she told Time. “I had not made Lady Bird yet. And he said, ‘I don’t think they’re ever going to hire you for this.’ And I said, ‘Well, they have to.’ Then, I was able to go talk with them about my ideas, and they did hire me to write it, and it was after Lady Bird had come out that I heard that they would like me to direct it, and did I want to do it? And I kind of had that— ‘Would I? I’ve been waiting 30 years!'”

Source: https://www.buzzfeed.com/jenniferabidor/greta-gerwig-barbie-facts