The James Bond casting director for more than 40 years has explained why the producers have never cast a “younger” person for the lead role. Speaking to RadioTimes, Debbie McWilliams–who has been the James Bond casting director since 1981–said younger actors who tried out over the years lacked a level of “gravitas” required for the role.

“We did look at a lot of younger actors and I just don’t think they had the gravitas, they didn’t have the experience, they didn’t have the mental capacity to take it on, because it’s not just the part they’re taking on, it’s a massive responsibility,” McWilliams said. “So we kind of scrubbed that idea and went back to the drawing board and started again.”

Of course, “young” is a relative term. The youngest actor to ever play James Bond was George Lazenby, who was 29 during the filming of 1969’s On Her Majesty’s Secret Service. Daniel Craig, who played James Bond in five films wrapping up with No Time To Die, was 38 when he played James Bond for the first time in Casino Royale. Henry Cavill was 22 when he auditioned to play James Bond for Casino Royale, a film that McWilliams was involved with.

Cavill said he nearly got the role as the “younger” option before the 007 producers decided on Craig instead.

In the interview with RadioTimes, McWilliams said the next person to play James Bond after Craig will be the person “who’s best for the part.” The person who gets the part doesn’t need to be a big name, though.

“Timothy Dalton was known, but he was known as a Shakespearean actor, really. Pierce [Brosnan] was known, but that was basically from television. Roger Moore was known from television. Sean Connery wasn’t [known]–nobody had ever heard of him,” McWilliams said.

Craig, too, wasn’t all that well known when he was cast as James Bond, having mainly starred in lower-budget, smaller-scale independent films at the time.

In terms of who we know will not play James Bond next, Taron Egerton and Idris Elba have each ruled themselves out.

The next James Bond movie will be a “reinvention” of the character, and it could take some time to find the right person to play the role, series producer Barbara Broccoli has said. “It’s about a reinvention, and, ‘Where are we taking it? What do we want to do with the character?'” she said. “And then, once we figure that out, who’s the right person for that particular reinvention?”

The person who lands the role will be signing on for a decade-long commitment, and this requirement might turn some people away, Broccoli said.