Because I know we never get to see fastback SUVs from the same perspective designers (and regular car buyers) see them. Maybe now this experimental bodystyle will make more sense. It was a natural way of having concept coupe drawings that retained their on paper exaggerated proportions.
They were a very interesting risk that wont last much longer since the Macan and F-Pace are the eventual style for these future on-road performance utilities.
Slopebacks will be quite the curiousity when we look back on them.