I'd withdrew my design if the CH ranked down my entries without explanation/feedback. But, I will keep them stay if I'm sure I have the strong concept or the CH give me some feedback to revise my design.
To be honest, I'm not really like to see my design ranked out of the top 10. It's clear enough to me that my design is far from what CH need/looking for. So, I better withdraw them. Beside, I'm not brainstorming and sketching all day long for blue ribbon anyway.