Good news: sales are increasing. Bad news: exposure is also increasing, which means more people who won't like your book are also buying, reading, and commenting on your book.
Someone once pointed out that if your books don't have any bad reviews, then not enough people are reading them yet. I think this is probably true. In the last couple of hours, I've come across several prominent blog/article mentions about how awful the books ERAGON and TWILIGHT are. The mentions brought lots of head-nodding and agreement from other posters. Of course, on the other hand, I'm also guessing that some of the 14 million books Chris sold and the 42 million books Stephenie has sold have gone to readers who, in fact, DID like the writing just fine.
That may be the trade off. Like Babe Ruth with his home runs, he also had the most strikeouts. Both those bestselling authors have huge numbers of bad reviews. The good news is, they still represent just a fractional part of the overall readership' opinions, which are expressed both in fansites and with their wallets.
No author I know tries to write badly, and we all certainly hope we're getting better at it. But readers do have different tastes, likes, and dislikes. And practically NO ONE can push all the like buttons at once. But the broader your readership is, the more feedback you'll get. And even getting the lousy reviews means that new readers are still being reached - and hopefully, they'll be intrigued enough to give one of your next books a try.
If nothing else, at least the pictures are pretty!
To close, the spur for this post was a fascinating thread on a book blog, with some very well-reasoned commentary and a few polite critiques of my writing style, juxtaposed with a delivery of comp copies of the second Imaginarium Geographica book in Czech. One step back, two steps forward.