Here's why:
* Historical context: Cotton picking was a brutal and dehumanizing practice associated with slavery in the American South. It was forced labor, often under harsh conditions, and was a significant symbol of oppression and racial inequality.
* Usage: While "cotton-picking" can be used in a neutral context to refer to the actual act of picking cotton, it's often used as a substitute for stronger, more offensive language, particularly in the phrase "cotton-picking ___" (e.g., "cotton-picking liar"). This substitution is often intended to be derogatory and racially charged.
* Perception: Because of its association with slavery and the potential for racial prejudice, "cotton-picking" can be perceived as offensive by many people, especially those of African descent.
It's important to be aware of the historical and cultural context of language, and to use language that is respectful and inclusive. If you're unsure whether a word or phrase is offensive, it's always best to err on the side of caution and avoid using it.