Constructive criticism allows the queens to understand what they need to do to impress the judges and win a badge. Without this feedback, the queens are not given an insight into what they can do to win a badge/win overall.

I know we want the queens to win on their own merit, but the judges opinions are what matter most in this competition. You're not going to win a badge/be in the top two without impressing the judges. Thereby, if a queen needs to put more focus or attention to a part of their performance or drag throughout the competition, the queens should be privy to this information. Not providing them this information is depriving them of what they need to know in order to win.