I prefer to quote people on the merits of the information they are speaking of, otherwise I am in danger of making the logical deception (fallacy) known as the “genetic fallacy”. Arguments are assessed based on their merits and not on their origins, although their origins may sometimes provide context, which may add to the overall discussion at hand.
For example, I have a video on YouTube that has information from somebody on 4chan, but because it is 4chan, people stop the video, and leave a comment mocking me for making the video, and anybody who watches it, because the source material came from 4chan. While looking at the source can be beneficial to adding context about my video, the information in the video cannot be automatically discounted just because of the source.
Can you think of any examples where you have seen the genetic fallacy used as a means of countering an argument, or of poisoning the well before an argument can take off? What did you think about it at the time?
Graphic source: Wikipedia