unpredictable

Most of the books that I have really liked, I have had to read for school or uni. I didn't know before I read it that the book was really good. Other times, the book's reputation proceeded it, but with really good books, there's always a surprise about it. 

I don't think reputation is a good guide because I often find that I don't particularly like the books that are generally regarded as the best that an author has written, or among the best. I often like different ones. Like, with Dostoevsky, I preferred The Idiot and The Possessed to The Brothers Karamazov. With Dickens, I didn't even finish Bleak House but I've finished quite a few of his other long books, and I much prefer David Copperfield to Bleak House.