The qualities than are important in a book are dependent on the benefit the book wishes to impart. The style and devices use in a book should be judged chiefly with regard to thier effect on the what the book it trying to convey. The fact that the benefit of most works is subjective makes it difficult to give quantitative value to a work and the devices used in a work. The parts of a work can be evaluated as either adding to or detracting from the impact of the work but the absolute value of any work in depentant on the reader.
I think that anyone can name at least one book that was just awful and most people who have read it will agree. Thankfully one of the benefits of a bad book is the ability to put it down (or throw it against the wall) and stop reading.

I personally absolutely hate Steinbeck, but that is such a personal dislike that even I give the guy a ridiculous amount of credit for writing novels that were well researched and were written with realistic details and dialects. My dislike centers less around the fact that he didn't do a good job and more around the fact that I'm just not that interested in reading about the historical periods that fascinated him. I'm sure that this opinion will make a lot of people reading it feel sad for me.
The weird ones are the books where the author attempted to do one thing (and may have been successful to some degree) but succeed at something that may have been completely unintended. At the time the LotR was written, I doubt that Tolkien was trying to invent a new genre of fantasy literature, nor did he know that certain setting details would be used by so many others who were inspired by his works. I don't necessarily think that spawning an entire genre of literature was the series' greatest achievement, but it is something that I feel should be looked at more closely.
I feel that literary criticism and analysis is important as a way to better understand, appreciate, and enjoy a work not as way to assign an objective value to a work.
I feel that in some cases it becomes absolutely necessary to apply literary criticism to a work in order to even understand it and get through it with any amount of sanity intact. I absolutely love James Joyce and Virginia Wolfe, but if you don't understand that their novels are largely experiments in stream of consciousness, you'll find yourself wondering 'what's the point?' Indeed, Ulysses is a masterful work which is roughly 800 pages long which describes the day in the life of one man to the most minute detail. It even goes into bathroom moments. Formatting, headings, breaks, and other elements we normally take for granted are experimented with and placed almost randomly on the page in some places. The final 45 pages of the book is all one long unpunctuated block of text. Now, if someone who doesn't understand what the heck Joyce is trying to do with this picks it up and reads it, there's a pretty decent chance that they just won't get it. Or they might get it to a point, but miss out on many of the points they should be picking up as they read it. Without the existing literary criticism and the discussions that continue to this day on Ulysses, I have to wonder if it would have eventually been overlooked in favor of books that are simply easier. Honestly, without literary criticism, I have to wonder if there would even be any perceived value of Joyce and Wolfe.