The Economic Observer's Lifestyle section recently featured an interview with well-known Chinese author and racing car driver Han Han.
In response to a question about why his posts on Sina Weibo are all comparatively long, Han Han had this explanation:

In 2006 and 2007, I saw writing as a way of recording my life. I'd write anything.
Sometimes I wrote essays, other times I'd just write about whatever happened to be going on in my life at the time. But later, more and more people started reading my stuff and I thought I can't keep going on writing like this, because these are my works. So I started to be more serious about every piece I wrote, this also included my Weibo posts. Most of my Weibo posts are long, but there are some short ones too, but why don't you get to see any of these short posts?
Because when I'm writing short Weibo posts, I just can't control myself. In most of these cases I'm writing about something sensitive, and as soon as I've written the post it's blocked.
In my Weibo account I have a lot of short posts, but only I can see them. When I’m writing long posts, I will consider my wording carefully and thus they won't be so sensitive. My short Weibo posts are all highly sensitive, so a lot of them are never sent out.
...
I think it's great [that people think he only writes long posts]. I hope that everything I leave behind in this world is a great work and not just idle chatter, I don't want leave that kind of thing behind for everyone."