That effervescence actually made the simple performance video more difficult for the director. "It was the hardest video I've ever edited because every moment was great," he said. "Every moment that she was on camera, she was amazing. She's got an incredible quality about her. She gets the camera, and that's what it takes to make a great music video.
"She came out in these high-heel boots and I was going to say something to her about them," he continued, "but on her own she was like, 'I'd feel better in sneakers.' Her instincts are great. She has great charisma and personality."
He recalled discussing the video with the young star during a visit to her home, where she told him how much the song — which she co-wrote — means to her, and said that it's about an ex-boyfriend. (Cyrus told MTV News last month that much of the album is about ex-boyfriends.)
While Ratner declined to reveal who exactly that ex is, he gave away a significant detail — perhaps inadvertently — that seems to confirm the song is about Nick Jonas. Cyrus recently admitted, after months of unconfirmed speculation, that she dated Jonas for two years.
"She had me come out to her house," Ratner recalled. "She started showing me all of her personal items from under her bed that her ex-boyfriend gave her. So she pulled out his dirty socks and a bunch of photographs.
"The necklace she's wearing in the video is the necklace he gave her," he said. "She's wearing his diabetes or medical necklace."
Nick recently made himself a de facto spokesperson for awareness of the disease: Earlier this month, the group held a press conference where he said the title track to their new LP, A Little Bit Longer — for which he wrote the lyrics — is a "life song" where he addresses his affliction.
For his part, Ratner said he believes Cyrus has the talent and the attitude to make her not only a Best New Artist, but a career artist.
He also pointed out what he sees as her emotional maturity, and her comfort with being a 15-year-old superstar.