It's not clear that points systems like this really select for optimal benefit, though. They tend to be biased toward the qualifications that are already well represented in the country.
Looking at immigrants I've met, yes, qualifications count for something, but sheer hustle and ambition can play a role as well, and often those propagate into the next generation too.
In hiring decisions, I was told to try to select for potential, not qualifications. Points systems are the classical "select for qualifications" move.
I don't think anyone said they're optimal benefit. But on the whole increasing the education and income level of your immigration pool is going to be more beneficial to your country than the opposite.
Potential can be a part of the point system. You yourself made some sort of crude scale of potential when you were interviewing people. Nothing wrong with formalizing that.
Yes, it's considerably harder to administrate such a system in an objective manner. A points system has the advantage of being objective. But that doesn't necessarily make it fair or a well chosen policy.
I'd say it's impossible to administrate such a system in an objective manner. If you could administer it in an objective manner then you can quantify and formalize it.
A point system doesn't mean the parameters are well chosen but by it's very definition it's more fair then an interview without any formal requirements.
It’s fair to the country as the country is able to make informed admission decisions weighted by the needs of the country, rather than a take-all-comers model.
It’s fair to the applicants as they have a clear set of guidelines as to what they need to do to become eligible for admission. Need to learn English to boost your score (As in Canada)? Cool. That’s tangible and clear. On the other hand America’s system of, roughly speaking, “Indians need not apply” isn’t exactly fair to the applicants.
Note: a points based migration scheme doesn’t preclude for instance refugee admissions, and Canada’s system has a points escape hatch if a province nominates you based on their specific needs too.
Is it really fair? There are several countries with degree mills for things such as masters even when they do not show the competencies required for such degrees.