You just seem(ed) very dismissive of Quora in your example. I also think that your verbiage of "destroyed" is greatly exaggerated.
I think that, on average, you'll get a much more useful response on HN, because there is a general feeling of how to reply and what can be done. When you write a question on Quora, it doesn't feel like you create a discussion; you submit a ticket you hope people will be kind enough to answer (seeing that there is no incentive, i.e. reward, model in Quora whatsoever). The comments for each answer are just yays, nays, and cutesy remarks.
There's a reason I don't feel comfortable calling Quora a community, because the interaction is mainly from answerer to asker.
I think that, on average, you'll get a much more useful response on HN, because there is a general feeling of how to reply and what can be done. When you write a question on Quora, it doesn't feel like you create a discussion; you submit a ticket you hope people will be kind enough to answer (seeing that there is no incentive, i.e. reward, model in Quora whatsoever). The comments for each answer are just yays, nays, and cutesy remarks.
There's a reason I don't feel comfortable calling Quora a community, because the interaction is mainly from answerer to asker.