I've never understood it. Why do people want to be part of a discussion community, but then go to a thread, barely skim the OP, read no other posts, give your opinion and never look back at the thread later? What's the point? Is it fun to do this? I'm not saying you need to read every post in a thread, but at least make an effort.
Or worse, just giving a 1-2 word answer to a question posted by the OP? Do people not want to participate? Why would you give an answer and not explain why you said what you said?
It just seems like there's no point in being part of a social community that centers around discussion when you don't want to discuss anything. "QFT" or "/thread" and comments like that are the worst offenders of all. Personally, I don't post in a thread unless I feel I have something constructive to add and I always return to check for responses for awhile.
It's the whole point of forums!