This is an old problem I've had and noticed in the past with previous WordPress blogs, and now again with the new blog I created upon returning to WordPress to give it another chance.
WordPress knows about these problems, but refuses to acknowledge them and act on them to correct them, no matter how many people complain about them. Not good service. As is, I'm trying to find ways to work around these problems or otherwise ignore them.
I am now again being followed by blogs I consider to be spam blogs, but which WordPress continues to allow because WordPress refuses to agree that they are spam blogs. Also, what I and many others would describe as fake blogs. There has again been a huge and recent surge in fake blogs and spam blogs following me. There is no way to block them. But at least they are not publicly listed like followers are at Twitter where we can block undesirable followers. That's what WordPress needs. Handle Followers like Facebook and/or Twitter.
More intrusive and offensive is the abuse of the Like Button, most of which is done by people who only do so to attract readers to their own blogs. When I post a long editorial article that will at least take 5 minutes for someone to read, and it gets liked about 5 seconds after I posted it, because someone saw it in the WordPress Reader for key words or categories, then I know they did not like it because they actually took the time to read it. All of those Like Button abusers have About Pages flooded with Comments by people thanking them for Liking or Following their blogs. And in that way they too are giving themselves a free ad by abusing Comments allowed on About Pages, as well as abusing the Like Button.
I've realized there are two kinds of spamming. Aggressive Spamming, and Passive Spamming. The Aggressive Spamming is when someone directly posts spam in Comments, and most of that is automatically blocked. I've not had a problem with Aggressive Spamming at WordPress. Passive Spamming is when someone puts all of the spam at their own blog, and then tries to get you to visit their blog by Following your blog or using the Like Button to get your attention. That is a huge ongoing problem at WordPress. Even worse, it is being encouraged by WordPress under its social networking plan, which does involve and advise use of Comments under About Pages with use of Like Button to attract readers and Followers. So there is no chance WordPress will ever put a stop to Passive Spamming. All I can do is to ignore it as much as possible. It's a numbers game. It's about money and advertising dollars for WordPress.
The first time I left WordPress was because of a technical problem, which at that time could not be fixed. WordPress made a change, and then refused to admit that the change was causing problems for some users with certain browsers. Eventually, it was solved.
The second time I left WordPress was when readers began to ask me about ads in my blog postings! What ads? I hadn't seen any ads. I looked where they told me to look and could not see them! Then I signed out and looked at my blog from a different computer with a different IP address. I discovered my postings jammed full of ads installed there by WordPress, which I was blocked from seeing and knowing about while signed in and at my home computer for its known IP address. They tried to do it without telling me about it and without me knowing about it. They tried to hide it from me. That's what angered me, as well as some of the ads being offensive to me and the purpose of my blog. They gave me no choice and no notice. To stop the ads I'd have to get the paid version of WordPress instead of the free version. That's a risk I'm again taking. I might do the paid version, but I can''t afford it at this time.
The third time I left WordPress was because of excessive abuse of the Like Button. I was getting hundreds of false hits every time I posted something. It was a Passive Spam blizzard, which I could not ignore and did not have time to deal with. I wanted to respond to legitimate Likes, but most were from fake or spam blogs.
I don't know how long I'll stay this time. There's a new storm now of Followers and Likes with what I consider to be fake or spam blogs. It's an increasing irritation again.