Why does 'justify-content: space-between' in the .main-header min-width: 1025px media query create such a large space?

Why does 'justify-content: space-between' in the .main-header min-width: 1025px media query create such a large space in between the name and main-nav elements? They spread to the opposite sides of the page, which in previous flexbox examples, 'space-between' didn't make such are large separation between items.