It's just labor law, these are countries where job security is considered very important. As a result, a lot hinges on having an indefinite duration contract.
The same rule exists in France and you'll have a hard time getting a loan or even a rental if you don't have the sacrosanct CDI (Indefinite Duration Contract), or legal guarantors with one.
It may seem absurd in these edge cases, but it's a way of putting pressure on employers to either hire people for the long term, or let them go.
In this case, it's not necessarily a bad thing in 90% of cases either (because those that don't get permanent employment despite scoring ERCs are certainly very rare), it prevents people from being stringed along in a lab where they're not really building up a career, but rather setting themselves up to be 40 and unemployable, when they're eventually not given the job security the lab would have given 5+ years earlier if they ever intended to/could do so.
The same rule exists in France and you'll have a hard time getting a loan or even a rental if you don't have the sacrosanct CDI (Indefinite Duration Contract), or legal guarantors with one.
It may seem absurd in these edge cases, but it's a way of putting pressure on employers to either hire people for the long term, or let them go.
In this case, it's not necessarily a bad thing in 90% of cases either (because those that don't get permanent employment despite scoring ERCs are certainly very rare), it prevents people from being stringed along in a lab where they're not really building up a career, but rather setting themselves up to be 40 and unemployable, when they're eventually not given the job security the lab would have given 5+ years earlier if they ever intended to/could do so.