I re-read my favorite books all the time, usually about a year or several months apart.
One thing I've noticed about re-reading is that I usually catch things that I somehow missed before: new details, or new insights about a character, things I didn't realize the first time I read the book. There are a few books I read as a kid or teen that have new meaning for me now that I'm an adult; it's like I missed something that I just wasn't able to recognize because of my innocence or lack of life experience that just went right over my head the first time I read them...so I've noticed that books can change depending on the stage of life you read them in, too.
One thing I've noticed about re-reading is that I usually catch things that I somehow missed before: new details, or new insights about a character, things I didn't realize the first time I read the book. There are a few books I read as a kid or teen that have new meaning for me now that I'm an adult; it's like I missed something that I just wasn't able to recognize because of my innocence or lack of life experience that just went right over my head the first time I read them...so I've noticed that books can change depending on the stage of life you read them in, too.