Omg this is so true! When these two boys at my school take my lunch box and throw it around, I just say to my friend (who is a Sagittarius) " come on, leave them and in the end they'll get bored" in the end they have my lunch box back to me!
Maturity is more to do with the mind than with your age. Sure, your body physically matures. You cease to grow, you hit puberty. Mentally and physically women mature sooner than men, but mentally no one is mature when they turn 18.