What I can't understand is why some people seem to think they need to include the entire OP in a quote when they post a response. It just takes up space needlessly, as if you're responding in the thread, it's obvious what you're responding to.
That's something my mother would do, and she does it because she's not really all that technically proficient. I've seen other posters here mention that they don't know how to trim the text within the quotes.
I think in some cases people are confusing the "Quote" button with the "Reply" button.
I think it depends on how many responses there are in between the OP and person quoting the OP. If basically everyone between has been responding to the OP then no need to quote them. But if the posters in between have went off on a tangent, the responder might be trying to show they are responding to the OP and not the new tangent.
Another thing tangentially related, the posts you see when you respond to a new post might not be the same ones another person might see. It depends upon how often your ISP pulls in new info. So 1 person see 3 posts, another sees 5 and some poor person only sees the OP cos they have a less than worthy ISP
I try hard to remember that tidbit when I see 6 responses saying basically the same thing at the start of a new thread