The producer told the Evening Standard that Craig enables the audience to "feel [Bond] from a much more intimate place".
"One of the things about Daniel is he's let us into Bond's inner life," she explained. "In the books you get a look into his inner conflicts and fears and anxieties, but it's very hard to put that on the screen without making him look neurotic as a leading man.
"A lot of the books focus on accidie - this revulsion he had for his profession; it's not easy killing people. He [also] fell completely in love with Vesper and she betrayed him, so he realises, from that point, he can never be susceptible to a relationship again."
Broccoli also defended her choice to help cast Craig as Bond, a decision that initially provoked criticism among cinema-goers
"I think that's the trouble with the internet now," she said. "Everyone has an equal voice so people read something - supposedly written with great authority - and it's by a 12-year-old in a little town some place in the United States who's never seen Daniel Craig, doesn't know what he's capable of, and [it] starts this fire.
"And then it's given prominence, which is bizarre. Of course we were making the film and we knew what we had, so we just ignored it."
Skyfall, the 23rd instalment in the James Bond movie series, is directed by Sam Mendes and also stars Javier Bardem, Dame Judi Dench and Naomie Harris. The film, the first featuring 007 to be released in IMAX venues, is due to be released in the UK on October 26 and in the US on November 9.
Watch a trailer for Skyfall below: