You could've left JV the second you registered, and it would be just one of these forums that you don't actually frequent. But if you're reading this it probably means you're active and post every once in a while. But why?
Why don't you leave JV right now? What makes it so you want to stick around? Perhaps you have friends here, or it's just a boredom killer. Maybe it's the only forum you actually enjoy.
As for myself, I suppose it's something I do to pass the time. Even though I don't even post that much, I open a random tab every now and then, come over here, read a few threads and go back to whatever. JV is also the only way I can contact a few users, and I'd rather not forget about them.