As a non-native speaker I encounter this phrase from time to time (in podcasts and such) and I’d like to understand the use (beside the literal meaning which is obvious).
Why would you say that? or sometimes Why do you say that?
To me, that sounds almost rude, like rebuking the questioner. However, the context usually leads me to conclude that this sentence is to be understood neutrally, in the sense of “I am interested in the background of the question”.
How should the sentence usually be used? Or does it depend solely on the tone the phrase is used?
I think it can seem rude sometimes to unexpectedly alter the course of a conversation by expecting a tangential conversation. I interpret the question to be the same as another question: “What experience has led you to describe your view in that way?” Or “Can you elaborate and help me to understand your previous statement?”
With this particular question there is a sense that the speaker is admitting that it is difficult for them to understand the other person’s position. I think that this admission of ignorance can help people to be vulnerable in a healthy way.
I hope this has been insightful and not confusing. I enjoy thinking about your question.
I hadn’t even thought about that, but that might partially explain why I perceive the sentence as rude. From my own conversations, I’m more used to people “working through” the actual topic and possibly asking about the background afterwards.
Might be partly cultural also.