Every so often I see people posting on their blog's comment policy, and it's probably a good time for me to do so.
When I started, this blog was open to all. Over the past few years, I've blocked one or two IP addresses, and I started to ask for work verification for comments. Then I blocked another couple of IP addresses and started moderating comments.
Why? Because this is my blog. It's my personal rantings, ravings, musings and ephemeral thoughts. Some posts are more random than others, granted, but the important thing is that they're mine.
Some comments have been, well, mean-spirited. Being a Pollyanna, I'm glad that people are reading and participating, and perhaps they've meant something as a joke and I'm just missing that. But if a comment strikes me as detracting from the blog, it's not getting posted. Simple as that.