Saying “A fresh approach to technical computing” in front of Julia makes users feel that there are actual people behinds this, and imprinting the image of Julia as a product of passion and enthusiasm. But without this, Julia is just another tool they use.
I’m a little bit exaggerating here 
to make a point that any software is better if users can feel the warmth of a human being. And showing such a motto is a good way to do this.