flex-box allows you to address certain flaws of the floating system.
for example the alignment issue -> all elements need to be aligned based on their vertical-center.
or clearing the floats in an extra container or pseudo selector.
or having the elements inside the box automatically grow to 100% height.
things that annoyed the shit out of CSS-Developers the last decade actually have been addressed with this concept.
the Grid-System addresses the "classic layouting" one of my ex-girlfriends did graphics design and marketing so she actually explained me how they do it on paper by using grids to balance and position everything in the layout.
css-tricks.com/snippets/css/complete-guide-grid
css-tricks.com/snippets/css/a-guide-to-flexbox
they are both missing solutions we had to "pseudo hack" into our CSS that now are addressed so we have less CSS/JS to maintain by getting the same results.
At least that's my opinion
j
stuff ;)