Why do I abandon a book or series?

So, as a general rule, I finish books that I start. It takes a lot to make me put down a book half way through it. But, there are exceptions to this rule, and, since I'm in a bit of a book rut right now, I thought it was a good topic to look at.

I have to care about the main character/s. This is a pretty broad statement. What traits stop you from caring about a character? To me, if a character is repetitive in what they're saying (procrastinating about how you've fallen in love with the new guy but he's so mean to you every other page kind of thing) then it's a pretty big turn off because to me, they become almost shallow. Recently in the YA books I've read, the above example happens so often and it really puts me off. I think, the reason hero's like Katniss or Clary are so likable by so many people is because they actually do something. They don't sit and stare at the hot guy for 250 pages and then do something, which is a huge turn off for me personally.

This ties in with relationships - both romantic and friendships. The relationships have to be believable. If you've read any of my reviews, you'll see there is a pattern in the relationships that I well...ship. They all have a spark, some sort of chemistry. Take Clary from the Mortal Instruments for example. I love her and Jace together - the sarcasm they generate is brilliant and offers a lot of relief from what would otherwise be quite tense. What I love about Cassandra Clare's writing is that every relationship has some sort of spark. Clary and Simon's friendship is also full of sarcasm and humour and yet it's a completely different tone than when Jace and Clary are together. All of the relationships within The Mortal Instruments to me are really great examples of how characters should interact. Recently though, there have been a lot of relationships between that characters that have lacked energy. They don't seem to work - the romance in book 1 of the Mara Dyer series for example was a relationship that I had high expectations for and just left me feeling depressed. The characters didn't connect to me and this was the main reason why I didn't go out and get book 2 because I didn't connect with the characters and their relationships.

The plot has to be believable. Again, this is quite a broad point because, obviously, we're talking about fiction books. We're not in a dystopic world where society is split into factions but the thing is, the plot within that is believable. You know those moments in the middle of the book where the hero does or says something and you're just like - 'what? How did you reach that conclusion?' Those moments where you're on step 4 but the character has seemingly jumped to stage 44? This isn't as common now as it maybe used to be - a lot of time is spent on making sure the reader can keep up, but every so often I run into a book that just leaves me confused and it's incredibly off putting.

All of these things can make a book feel slow and clumsy. Which is the reason so many people stop reading a book or series and is the main reason I stop. I am willing to persevere with a book I truly am, but these are the main things that turn me off continuing. What do you think? Have I missed something? What stops you from continuing a book or series?

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