Why HN readers don't have a blog

Yesterday, I asked the Hacker News community why they don’t have blogs, even though they have the necessary technical skills.
Many Hacker News readers and contributors have the technical skills to run their own blog and post their opinions. But instead they prefer to use Twitter or other social networks. Why is this so? Is it the effort?
I want to respond to some of the answers in this post:
I don’t want an extremely public record of my personal opinions or thoughts today, because I know they...