With this though, I've been seeing some people say that they have stopped following anyone who wasn't their target audience, didn't have avid reader in their bio, or were authors. This is not a good plan for several reasons.
First, let me touch on not following people because they are not your target audience. My target audience are girls ages 11-16. However, many of my readers are older than that and even boys as young as 12 have enjoyed my book. Now, much of my target audience cannot get Twitter or Facebook. More and more parents are either restricting this usage or forbidding it altogether with the uprising of cyber-bullying. So, I have connected with many people who have passed my book along to their children. Some parents are not into reading Young Adult nor fantasy, but know their children are. You wouldn't have known this unless you were following them and made a connection.
Secondly, not following someone because it's not in their bio can be a big mistake. Many people are readers. I firmly believe that everyone would love reading; it's a matter of finding the right genre. Some people are readers, but are not very public about it. I can relate. I love to knit, but I get a bit shy about it because it's usually associated with little old ladies, which is totally not true. But anyway, reading, especially for my target audience, usually implies nerdiness. When did being intelligent become uncool? No rambling. Okay, so point is you never know where your target audience will pop up. I think disregarding someone for what they right in their bio can potentially throw away a reader. You just don't know.
Lastly and this truly, truly bothers me, not following someone because they are an author. Sorry, but I have to say it. WTF?!?!?!?!?! To be a writer, you have to be a reader. These two words are synonymous. You cannot be a good writer unless you love reading. Not just love it, but it's a passion. Most writers write because they want readers to fall in love with their books as they've fallen in love with other books. My love for reading didn't stop when I began writing. In fact, writing has been a part of me from the moment I began reading. This is a momentous mistake. Other authors are tremendous. They help promote you in any way they can because they know what it's like to be in the trenches. Finding authors that are in your same genre are even more beneficial. They are not competition. As I've said before, what reader only reads one book? Making connections with other writers in your genre can double your promotions. It's a win-win situation.
Unless I'm missing something, not following these people will only hurt you. There are a few not to follow. Don't follow those that say want to increase your followers; they will just be deleted and have spam tweets. Also, no need to follow those who have never tweeted even once. Twitter etiquette these days is to follow your followers; it's only polite. Unless you are a celebrity and have millions of followers. :oP
There are a few things not to do though. Don't randomly follow people. That won't help. If you are going to follow people, find people you truly want to follow and want following you. Expect that only about 30 of every 100 will follow you back(Rough estimate). If people have high followers and they follow less, chances are they won't follow you. I have about 40 people that I follow that I know won't follow me. That's okay, they are on my celebrity list.
How I do this: (Twitter Tip) Lists are your best friend. I'm not the best at keeping these up to date, but I do go to them when I am helping promote authors or keeping in touch with people. Following all of your followers, will make your home overcrowded, so lists help keep that controlled. I, also, use tweepi.com. It is an incredibly useful tool in so many ways. First, following your followers, you will run into a follow limit. To free up room, Tweepi helps me unfollow those who don't want to follow me. (Don't take offense if someone doesn't want to follow you. Many people use their Twitter profiles for friends and family only.) Then, Tweepi helps you to find followers that may be in your target audience. It is always a gamble, but I have made very useful connections using this.
The most important thing is to always make connections. If you are like me, this will be your hardest challenge. I am a face-to-face kind of gal. Making connections is a bit more work and more difficult online for me, but if I can do it, so can you. :o) Hope this helps.
Lots of <3,