Blogs that were do follow going no follow now

Mostly bloggers are just selfish. They will leave the blog comment section open for the first few months or even year and give do follow backlinks to all and that will attract many useful comments. Then, they will simply make ALL links no follow. That way they get everything they wanted and you end up with nothing you wanted, such as a backlink. It's tricky but you can't really do anything about it.

Do follow blogs attract spammers. The no follow attribute ensures that only people who really want to participate, rather than getting a backlink will comment.

Well it's very simple no one want's to share their link juice with anyone other especially low quality website because if they are giving you a do follow link they are sharing their pagerank with you

- Sunil Bishnoi

Why not just keep the blog moderated, so all comments must gain approval but allow the blog comments that gain acceptance to have do follow links? That will encourage higher quality comments, rather than simply making all comments with no follow links.

Even if all your blog comments and backlinks are no follow, they still serve a useful purpose by being promotional, meaning they are likely to attract people who will click on the link to visit your blog. These people will actually be the best reason to post blog comments, rather than simply trying to get a backlink.