Why do you use "best books" as a motif for the title?

We use the “best books,” or "best science fiction books," or "the funniest books," or "the most hilarious" motif because 95% of book searches on Google include that phrase. And, instead of fighting that huge trend, we decided to go with it. 

In user testing, we found that users think that way when looking for a book in a bookstore as well, even though they don’t mean “best” objectively but rather someone's favorite. 

I know this makes some authors nervous, but please understand this is not a literal phrase but rather a subjective one. I think this trend is due to the internet/Yelp effect. When you ask someone where to find the "best Thai food," you don't mean the best Thai food objectively in the world; you mean their favorite.