The point is that if you come from a low income background, there is a very good chance you will never make it to university, because you will probably never quite make it to gymnasium (or through it) to begin with.

For those who speak German:

http://www.sueddeutsche.de/karriere/uebertritt-aufs-gymnasiu... (süddeutsche.de)

https://de.wikipedia.org/wiki/Bildungsbenachteiligung_in_der... (de.wikipedia.org)

http://www.zeit.de/2010/06/C-Uebergang (zeit.de)

In English:

https://en.wikipedia.org/wiki/Education_in_Germany#Determina... (en.wikipedia.org)