'Unfortunately, I know quite a few people that didn't make it,' Mr Berjavi said during a break between classes.

Germany's tuition-free universities have long been attractive to students from the developing world. But dismal graduation rates for foreigners are prompting criticism that the country is failing to properly select and prepare prospective students from abroad.

According to a study by a non-profit education organisation, only a quarter of all foreign students manage to graduate from German universities. Those lucky enough to get a degree normally take an average of eight years to do so. Countless more hopefuls are unable to pass entrance exams.

For students from outside the European Union, failure to get a university spot first time around carries dramatic consequences. Most face immediate deportation after their visas expire.

Like many foreign students, Mr Berjavi was sent to a university preparatory school, or Studienkolleg, when he failed the engineering course entrance exam.

The preparatory schools offer instruction in German and other subjects, helping hundreds each year overcome academic or linguistic deficits. But there is increasing pressure for their overhaul.

'We really need to develop another system for picking students,' said Jochen Hellmann, director of the University of Hamburg's international programmes.

'We need to focus less on the qualifications someone may have on paper, and instead determine what they are really capable of doing.'

Dr Hellmann is among those calling for a wide-ranging reform, including giving the preparatory schools more discretion and input on the selection process. Currently, a central office sets the criteria for non-EU students who want to study in Germany. That bureaucratic arbitrariness encourages some simply to take their chances by travelling to Germany.

'Since there are no tuition fees here I thought I'd come and give it a shot,' said Kim Dong-young, a 29-year-old Korean studying product design at the University of Applied Sciences near Berlin.

'I just barely made it. My visa was running out.'

One option being discussed is increasing the number of students that are tested before they leave their home countries.

Associated with the University of Hanover, the German International School in Jakarta just graduated its second class of Studienkolleg participants.

School director Ekkehard Zeeb said the programme was launched because many Indonesian students were failing to qualify for spots at German universities. Dr Zeeb said although the 12 prospective students in Indonesia each had to pay about Euro3,600 (HK$35,700) to cover tuition costs, the programme often worked out cheaper than spending time at a preparatory school in Germany.

Still, unless there is a concerted effort to increase the number of such facilities abroad, most foreigners will be forced to gamble, like Mr Berjavi and Mr Kim.