Rob laments about a book and wonders where to stop reading. It's a hard decision to make and I've seen (and discussed) this with other reviewers before. Me personally, I prefer to use the 10% Rule. Simply put, I'll read the first 10% of the book and if it is still entertaining, I'll continue to read it.
I just tend to ignore my own rule though. I'll read, to the end, nearly every book I pick up. There are a few exceptions, but I do like to finish what I start. It's like sex. The first 10% is foreplay and I certainly don't want to stop there. I need to finish to see how it turns out. It may be horrid, but it may be the best ever. Besides, I don't want to get Blue Book, right?
Yes, I realized I just compared reading to sex. I was speaking metaphorically, not literally. And no, my jokes usually aren't funny, so if you didn't laugh, you were probably in the majority.