Quote by Terry Pratchett
If you really want to upset a witch, do her a favor which she has no means of repaying. The unfulfilled obligation will nag at her like a hangnail.
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Summary
This quote suggests that witches, beings associated with magic and supernatural powers, have a strong sense of reciprocity. By helping a witch without any chance for her to repay the favor, it creates an unbalanced dynamic. The unfulfilled obligation causes a lingering dissatisfaction for the witch, similar to the annoyance of a hangnail. This quote underscores the importance of maintaining balance and mutual exchange in relationships, even those involving mystical or fantastical beings.