Is Being a Good Writer Important?

No info-dump, show- don't tell, avoid adverbs, no passive voice, beware of repetitions. You've probably come across these writing rules. We treat them like the unbreakable rules. This is Writing 101.

Are they as important as we make them out to be?

I'm currently reading a book that had a major info-dump in chapter 2. Let me repeat that...in chapter 2. We don't care about any of the characters yet and the author pulls us out of the story. I was seconds from quitting that book. The chapter was so boring and unnecessary. The lure of a shy, socially awkward female protagonist kept me reading.

Info-dump is universally considered a major no-no. Putting it in chapter 2-all of it was backstory- is like asking people to stop reading. I checked the reviews for this book. I couldn't possibly be the only one bothered by this. Turns out, I was. People loved this book. No one cared about the info-dump in chapter 2. This author got a ton of glowing reviews on Goodreads and Amazon. They aren't in the thousands. Considering how hard it is to get reviews, over a hundred is pretty good. 
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A while ago, I bought this fantasy book. It had a great cover, awesome concept. The reviews were hailing it as the best thing ever. I was excited about reading it. I started it. I could not get past the bad writing. The author did no showing. It was all telling. The story did a whole lot of "I looked and saw." This bothered me...a lot. I went back to the reviews thinking I couldn't be the only one annoyed by this. I was. People talked about the plot, the characters, the world building, pacing. No one mentioned or cared about the amateurish writing.

These are the most recent examples. I've come across many books that tells instead of shows or stories where the author found a word or phrase they liked and used it to death. Despite that, people enjoyed those stories. 
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As you probably know, 50 Shades of Grey has a movie coming out next year. I haven't read the book, but from what I heard, it's not the best written story. I learned in a workshop at the Writer's Digest Conference over the weekend that this book has sold millions of copies.

One of my favorite series is The Broken Empire by Mark Lawrence. It breaks all the rules about how to handle backstory. People love this series. 

Most of these rule breakers aren't self-published authors.
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We hear all the time about hooking the read on the first sentence. I can't recall the last time I read an interesting first line or even a memorable opening scene. In the land of ebooks and online shopping, I don't think that matters. I never use the "Look Inside" feature on Amazon. I've read books that dragged for 2 or 3 chapters before they got interesting. 

On the flip side, we have insanely popular series like Harry Potter and Game of Thrones that are well written. Although, I have caught some adverbs in Harry Potter. At the conference I mentioned earlier, I learned it's not so much about the writing. It's about our ability to tell a story. We've gotten it in our heads that there are things we have to do in order to tell a good story. You can write a book that avoids every single thing that annoys readers- culling needless words, no adverbs, trickling backstory a little at a time. You're still going to get someone who doesn't like your book. You can't please everyone.

I always knew we could break some rules in writing. I assumed, show- don't, tell, no-info-dump, stay away adverbs were the few hard and fast rules. Knowing that I can break them and still write a book people love it a bit freeing. I've heard the avoid using the verb "to be" rule. Never understood it. I'vw come across many highly regarded books riddle with "was" and "were". I know what I like in a story and I'll write that. I'm writing simply to entertain readers.

What do you think? Are the rules of writing still important?