I'm pretty sure the point of it being changed is so the constitution is better suited for the time period and the lives of the people that live under it. If the constitution wasn't able to be changed then we'd be living with the same rights we were supposed to have back when it was originally written, and that's kind of scary because a lot has changed since then. The document was written during the revolution and during a time when people were much less equal then they are today. If the constitution wasn't changeable it wouldn't apply to a lot of aspects of our lives now as our lives now are different than George Washington's