Marketing communication is inherently secretive. People have ideas that are only valuable if nobody knows them until its too late to do anything about them. The first mover's advantage is debatable in the product arena. But it is fact in marketing communication. If I have an awesome campaign line, and you find out about it and put in out there before I get to, you have reaped the entire potential value of my idea.
This creates and interesting paradox. Marketing people tend to be the types of folks who like to talk. Some like to share. Others like to brag. But in general, we tend to be talkers. Yet, our stock in trade requires us to keep secrets. Also, just about anyone who has worked in an agency has been in a position to have to keep client secrets. We keep our clients' secrets. Our clients keep our secrets (and our clients' secrets). Secrets flow downhill.
I have a friend whose dad was an Air Force pilot. Flew the decoy for Air Force 1. Was privy to the president's travel schedule. They lived next to a CIA guy. The two dads would have strange, cryptic back fence conversations. Both making allusions to secrets. Neither actually talking about them.
Right now, I know three big client secrets and one big prospect secret. I'm sure I'm not unusual among people in my position. But they're not telling. And neither am I.