Economist and liberal New York Times columnist Paul Krugman reveals why he doesn't use Twitter to tweet with his fans. He writes in a blog post:
[M]any people end up destroying themselves by tweeting something really offensive.
Why do people do this? Well, it turns out that many prominent people have inner demons of one kind or another — often homophobia, but also racism, sexism, or just some kind of generalized contempt for large numbers of other people. And social media make it all too easy for those demons to slip out in front of a large audience.
I don’t think I have any demons like that, but who knows?