I saw a Facebook post this morning where an author said they don't want to be told what to do anymore and that she would do what she wanted to do (or something like that). I'm not really sure what this was about, but the posts that followed that one made it look like her comment had something to do with book reviews or being told how/what to write.
Here's my take: In writing, there is a formula. You either follow that formula or you don't. Those who follow it have a greater chance of success than those who don't, so why not follow it and improve your earning potential? Reviewers help you zero in on that formula, because, like it or not, reviewers have the power to influence who buys your book and WILL follow the formula, even if you (the author, in this case) don't.
Yes, the writing formula works on the reading end, too. The readers dictated the formula, after all. The readers are the ones who said they like happy endings over sad ones. The reader likes seeing the characters overcome obstacles to reach their objective. The readers like strong characters who jump off the page instead of ones that are weak and flimsy. The readers like alpha males and strong-headed females. The readers like angst, conflict, tension, adversity, and a whole host of other things. So, if you deviate from what readers want (the formula), you risk not having any readers.
If an author doesn't understand this, they don't understand their business. And writing is my business. I'd better understand it and work hard to learn all I can about it, or I will sink in a sea of authors willing to give readers what they want. And like any business, you have to give the customer what they want or they will go elsewhere to find it.