it depends on the topics

right now I'm not posting in some cause the topic but I'll jump back to it later when the topic changes

Sometimes I just wait
Sometimes I randomly shitpost because who knows
Sometimes I'm posting relevantly

*is lurking*

-flops onto mem-

*panics and flails*

-is flailed-

For me, I generally join hangouts either because the person that opened it is someone I talk with in other threads (like with mem's hangout) or because the hangout has a specified topic that interests me (like the hogwarts hangout).
If it doesn't have a topic and I don't feel like I know the owner already reasonably well, I tend to be shy about posting.
It depends a bit on how the opening posts are written, too, if they explicitly invite random people to just jump in and chat, that makes it easier for me.

And of course I didn't want to say that posting about a different topic than what the current conversation revolves around is necessarily bad! I just find it difficult to respond to when it's something random that also doesn't really lend itself to further discussion - like the "I like ice cream!" example Akili gave. I mean, sure, I could ask about what your favourite flavour is, but if you made no indication you wanted to discuss ice cream flavours and there's actually a working conversation going on in the thread, why would I really want to?
If it's a post not connected to the current topic but that contains enough meat to start a new conversation, that's fine with me.

I just realized that whenever I see a random post I still try to engage a conversation. Although I'm bad at it myself xD The other problem is such random post owners vanish without a trace a lot of the times XD

It's hard to start a conversation with people who just vanish :D
Maybe sometimes it is because a few people post something ignoring them and they give up before you try to engage them and don't look at the thread again?
Sometimes it's probably also just people forgetting where they posted. Unless you bookmark all threads you post in, I don't know of any convenient way of looking at them... We don't have any "threads you posted in" button anywhere, do we? I've seen that on other forums, but not here.

speaking of vanishing, I'm not going to have much time to be online from... well, yesterday/two days ago until Saturday or Sunday, depending on how things go. No reflection on any of you fine folk, I'm just a bit preoccupied.