Pop!

On November 14, 2011, writeforfun wrote, ...I've already read your extremely helpful section in Writing Magic about developing characters and I've filled out a character questionnaire for each of my characters, but they still seem sort of flat and Mary-Sue like, especially compared to the ones in my last book. I think part of my problem may be that they don't have lots of quirks and faults, despite my efforts to think up some and apply them. Any ideas on how to make these characters pop?
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