The most common and most likely answer to this crossword clue is the 14 letter word DISCRIMINATION
I've seen this crossword clue in The Sunday Telegraph
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More clues leading to the result DISCRIMINATION
Buddy explains!

The straight part
We know that "good judgment" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case good judgment = discrimination.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DISCRIMINATION mean?
DISCRIMINATION noun- Discernment, the act of discriminating, discerning, distinguishing, noting or perceiving differences between things, with intent to understand rightly and make correct decisions.
- The act of recognizing the 'good' and 'bad' in situations and choosing good.
- (sometimes discrimination against) Distinct treatment of an individual or group to their disadvantage; treatment or consideration based on class or category rather than individual merit; partiality; prejudice; bigotry.
- The quality of being discriminating, acute discernment, specifically in a learning situation; as to show great discrimination in the choice of means.
- That which discriminates; mark of distinction, a characteristic.