All my knowledge about attachment theory was based on a couple of social media posts I had seen float by over the years. I wanted to get a deeper understanding of what it's all about, and Attached successfully provided me with that.
However, it's not a very good book. It's fairly one-sided, a bit shallow, and quite repetitive.
While it's a good introduction to the topic and actually made me think differently about a couple of very fundamental things, I just can't rate it higher than this.