This is another example of perverse, unintended consequences of "pro-worker" initiatives biting their intended beneficiaries in the hindquarters. Take a look at France for the endgame to that: between generous benefits and legally guaranteed protection from firing that makes Japanese salaryman positions look unstable, the economy is structurally incapable of employing a huge percentage of the work force. The young and immigrants, who are the worst affected by this (not surprising: the lowest skilled/lowest educated/poorest always catch the worst of every systemic economic issue), have little to do but sit on the dole or riot, and few prospects for ever doing anything else.
My impression is that similar issues cause the massive underemployment of the non-salaryman strata of Japanese twenty-somethings. Many of the freeters (people who bounce from part-time job to part-time job) are cut out for entry level work, but hiring someone is a lot like marrying them, so if you don't have the appropriate credential and a resume which looks like exactly what the company wants, they generally pass.
My impression is that similar issues cause the massive underemployment of the non-salaryman strata of Japanese twenty-somethings. Many of the freeters (people who bounce from part-time job to part-time job) are cut out for entry level work, but hiring someone is a lot like marrying them, so if you don't have the appropriate credential and a resume which looks like exactly what the company wants, they generally pass.