Hovedårsagerne til disse forskelle skønnes at ligge i såvel arbejds­markedernes funktionsmåde (E. Verdier) som arbejdsmarkedsparternes håndtering af problematikken vedrørende de unges erhvervsmæssige indslusning (R. Zedier)
The ways in which labour markets operate (E. Verdier). the ways in which the social partners tackle the issue of integrating young people (R. Zedier) and public job creation initiatives (C. Borgomeo), seem to be the main keys to understanding these differences.