Not getting “it” means not getting why great work is not only important, but also imperative. Not getting "it" is a malady that includes creative personnel as often as other departments. There are plenty of creative people who blame everyone but himself or herself for poor work.
The key is to do something about those “not getting it” quickly so your agency doesn’t lose momentum. People who are not quite up to speed can only adjust if they know where they stand. Tell them. Don’t hide your disappointment until it boils over.
I have a former co-worker who went through this experience when she went to work for an agency that is one of the hottest in the industry. A unique media need brought her to the conclusion that the assignment couldn’t be successfully completed. Her supervisor immediately sat her down and clearly explained what was expected of everyone at the agency. She said that there was no such word as “no” in the agency’s vocabulary. Whatever the challenge, one found a way to make it happen. My young friend instantly responded by trying again and solving the problem. She has been there for several years now and loves her place in the sun. I really admire her and her agency for their attitude and approach to success.
I’ve had a few people work for me that surprised me in such a way. Thus, I try not to judge who’s going to be the star. Sometimes a duck becomes a swan. Similarly, I don’t wait too long for the swan to blossom. People, who know where the bar is and never try to jump over it, assure the bar will never get raised.