It is amazing, but in today's world, it is so easy to throw the blame at a lack of a solution, or the reason a problem is occurring. We see this in politics now. It is the Democrats' fault. It's the Republicans' fault., it is ... I think you get the idea. In education, we blame the teachers or blame the students, or blame the environment. And yes, the same thing happens in publishing.
I do not go a single day without seeing some post by an author on social media blaming someone else for the lack of their book getting picked up by an editor or agent, or blaming someone else about book sales. While these might be the reasons for something not happening, it is always important to ask yourself:
Am I part of the problem too?
If you are not liking how the sales are going on your book, what steps are you personally taking? For example, if you publisher does not seem to be pushing your books as much as you want through social media outlets, aren't these things you can also do? You have the same access. You can do the same art work with your covers. So, step it up!
Let's talk about book covers and titles. If you don't like what you see, are you bothering to say anything about it? I know the publishers I work with have the authors provide extensive suggestions and consider those ideas. If you feel that you don't have any say, you are really mistaken here.
Now, let's talk about submissions. If you are getting a lot of rejections, I hate to break it to you, it is not the world working against you. There is likely something you are doing. Submitting to the wrong person? Not working to a market? Not reading the guideline? (NOTE: Most of my rejections come from these problems).
The deal is, you ARE part of the equation. Spending all of the time complaining about things is not going to get you anywhere. Blaming other people is not going to get those book sales going. You have to take charge.