You can make new friends from all over the world by visiting new countries.
You will get a certificate called "Youthpass" which is good for your CV.
You can try out what kind of job suits you and gain work experience.
You have time to find out what you really want to study.
You will get pocket money and money for food.
You don't have to search for accommodation.
You will have health, property and Travel insurance.
You will become more independent and self reliant.
You will have free language lessons, trainings and time to work on yourself.