Posting: There will probably always be an on going debate of when and how often to post. I stand by my philosophy of knowing and understanding your platforms analytics, to better understand optimal days, times and how often to post but on average 1-3 times a day 3-4 times a week seems to be a good start. If you are not getting any action on your platforms, it could be that you are over posting or under posting. Nobody wants their feeds filled with nothing but content from you but also the audience members that really like what you have to share would like to see more than 1 post a week from you. So really study and learn your analytics and post at the right times for your audience and your business.
Platforms: If you are concerned about the lack of response you have on your platforms, it could also be the platform you are using. You do not need to be on every single platform. Deciding which platform is best for you will be decided by the type of business you have. You will also have to do some testing with different platforms to see where you get the most engagement. Stick to 1-3 platforms, don't spread yourself to thin. Focus on the ones giving your the best response.
Your Business: The type of business you have will play a big role one how people respond to it on social media. Believe it or not, not every business should be on most social media platforms. I do believe that no matter what your business is, every business should at least have a Facebook Business Page why? Well, it being the #1 social media platform in the World with over 2-billion signed up and +1.8-million active users daily, why wouldn't you want to be a part of that.
Even if you have very little to zero interaction on Facebook, you should still be on it and actively using it but in general, there are many businesses out there that people prefer to interact with, in a face-to-face manner. There are businesses out there that require that one-on-one touch and no matter how good you are at posting great content, your business just may be one that does better with traditional marketing versus social media marketing. Know your business, test social media against traditional marketing, ask your customers/clients in a poll and choose the right marketing path for your business.
You, You, You: Finally, the problem with the lack of engagement might possibly be you. You may think that your content is great but really what's lacking in your content is you. For whatever reason, your personality doesn't shine through in the content you are sharing. Even if you are sharing an article you saw on another site, related to your product or service, all you do is post it. Where are your thoughts and feelings on the subject? Before posting, talk about why you are sharing this info, let your audience know how you feel about the subject, ask a question about it and get involved with it so that your audience will too.
Another problem might be that you are really busy with your business so you hire a social media manager to take care of the posting for you and that's great not a problem with that at all except for the fact that nobody, I mean nobody knows your business like you do. Even though you have someone managing your platforms and posting for you, you have to get in there every now and then and show your audience that you are there, you are real. Share your thoughts and feelings, show pictures of your weekend family get-a-way, share your personal and business story. Remember your social media manager can't do that for you, they are there to assist you. It's your business get in there and make it happen.