As writers, it's important to learn and understand the rules and principles behind what makes good fiction. It's important to apply those rules and principles to our own writing. It's important to be able to recognize those principles when other writers use them (or fail to use them) in their writing.
But it's also important not to let our knowledge of those rules ruin our ability to enjoy a good story.
As we start to really gain some knowledge of how the writing world works and how fiction works, it's easy to start getting a Barney Fife attitude about it. We get all swelled up with confidence and self-importance and next thing you know we're standing at the ready to pronounce judgment and doom on any pleb so foolish as to break one of the sacred laws that form the code of good writing.
We writers have a tendency to get tunnel vision and focus way too much on the rules, however. We often conclude that a book is terrible because the author broke this rule and that rule and how did such doggerel ever get published? If you're still in the frustrating process of trying to get published, such cases are doubly infuriating because you, of course, know much better than to ever commit such literary sins so you should be getting published instead of these buffoons! (That J.R.R. Tolkien--who does he think he is?)
I hear ya, and I feel your pain. Truly I do. But calm down for a second and ask yourself: Did you enjoy the story?
Sit down and pick up your favorite novel--the one you read over and over and never get tired of. Start reading it with nothing in mind but finding writing mistakes and literary sins. It may be a few chapters before you find one, or you may find one a paragraph in. Gasp!
Now pick up one of those enduring classics--you know, that book that's been on the NYT Bestseller list for the last 300 years. Do the same thing: start reading it with finding literary sins as your sole purpose. How long does it take you?
So let me ask you this: have a few broken rules destroyed your ability to enjoy that favorite novel over and over? Have they dampened the success of that enduring classic?
At the end of the day, novel writing is an art, not a science, and what makes a great story is just that: a great story, not a perfect adherence to the rules of good fiction.
Lord of the Rings, Pride and Prejudice, and Sherlock Holmes don't endure and remain popular because their authors followed all of the writing rules flawlessly. (Come to think about it, have you ever heard any work of fiction praised in the media for that reason?) They remain popular because they tell an epic, inspiring story, or because they speak a bold message to the culture, or because they challenge readers to think in new ways.
Once you know and understand the rules of writing, it is hard not to notice them in other people's writing. And I'll admit that once in a while a book does make it to publication that I simply can't stand to finish because the quality is so poor. It happens. But those cases are rare--almost as rare as the book that contains no mistakes of any kind whatsoever.
So chill out, Barney. Alright, so they broke Ordinance 4861 Section a.) Paragraph 3 of the Good Writing Technique Manual. But they told a great story, didn't they?
And isn't that what you read the book for in the first place?