what is wrong with getting married too young,

I'm 19...what if I got married when i was 20?

I know that you need to be financially stable, be on the same page as you husband, what similar things in life, have similar goals...have the same religion or beliefs help, being able to work together and be sacrificing is important as well

If I ahve all of these things...what is there missing??...I just don't understand what is wrong with getting married if youa re willing to work hard

could someone who is experienced possibly fill me in...much appreciated thanks