I find it rather fascinating that a director like Francis Ford Coppola would claim imagination as his biggest asset. We know how much money and talent he has. He could probably pull strings on the moon if he had to. Naturally, the guy who made Apocalypse Now and The Godfather won't face much challenge getting his next production made.
I wonder when he said it... Do you know the year? Was it a publication? TV interview? Red carpet event? But I really would like to know when. Was it at the beginning of his career or more recently?
I say this because I feel that many filmmakers out there also have a brilliant, colorful imagination. But no one can make a film with imagination alone. You need money and talent, both of which Coppola has.
Nevertheless, his comment is savvy. I think all filmmakers have a powerful imagination. You need that not only for storytelling, but camerawork and editing as well. Let us learn from the master... imagination it is.