Countries that rely on income from natural resources are worse off because they tend to neglect everything else that might generate wealth; also with these countries a small elite tends to get hold of the oil well, this leads to authoritarian rule and other goodies.
A windfall from oil often turns out to have many toxic side effects, so it was a very wise decision to stash it far away, as far as possible.
i think they want to avoid the resource curse/paradox of plenty by taking the oil money out of circulation.
https://en.wikipedia.org/wiki/Resource_curse
Countries that rely on income from natural resources are worse off because they tend to neglect everything else that might generate wealth; also with these countries a small elite tends to get hold of the oil well, this leads to authoritarian rule and other goodies.
A windfall from oil often turns out to have many toxic side effects, so it was a very wise decision to stash it far away, as far as possible.