This song is actually about how Paramore almost split up in 2008. And how they realized that they were very lucky people to be in such a successful band that they were taking for granted. It's about how the band began to like eachother again because they were living together day in day out and they we're getting sick of eachother, but they then resolved their problems from writing the album.
Brand New Eyes is actually all about what Hayley thought of the rest of the band members whilst they were arguing.