Mean is a response to those people who find every opportunity to put Taylor down. She expresses how she will never be able to impress them and they always point out her flaws. She promises that one day she will be so big that they won’t have any effect on her.
We have all been there. Being enchanted by someone secretly, but too scared to tell them. It’s like having a high school infatuation all over again. This song perfectly encapsulates that feeling.