What makes you reread a book?

Are you a rereader? 

This is a question that most people answer easily as either yes or no...for me I'm going to say sometimes.  At times I feel like my TBR pile is too big and there is no way I have time to reread a book, but other times I find myself rereading one anyway.

 

That got me thinking about rereading and why I tend to reread (or read, then listen to the audio or even listen to the audio twice) some books and not others. 

So what's my critierion (it has to be one of the following, but not necessarily all of the following):
1. It's one of my favorites
2. I forgot what happened and/or I want to read the next book in the series
3. The movie is coming out
4. I heard the audio was amazing
5. We are discussing it in bookclub that month
6. I've joined a read-along

So that brings me to you...What makes you reread a book?