Saudi is trying to industrialise. Specifically, it's trying to move from a nomadic, tribal, semi-agrarian culture to an urban, technological, capitalist one.
It wants to do this while remaining an absolute monarchy, which means the ruling class has to change from a royal family to a band of mutually hostile businessmen who happen to be closely related - and who collectively form a one-party state. I'm not sure they fully understand this themselves.
Capitalism doesn't need a lot of capitalists. It doesn't necessarily need high technology. But it does need a lot of workers. So who does the work in Saudi Arabia?
The owner of the building where I work is a Saudi businessman. All the two dozen who work for him are Sudani or Indian. Outside sweeping the streets, working in the auto-repair shop, and serving in the restaurants opposite, Pakistanis and Lebanese. Operating the hotels and shisha-houses, Bangladeshis and Philipinos.
There's a lot of building work, which means not just builders but plumbers, electricians, carpenters etc. Of those I've met, none were Saudis, and of the remainder I've seen, none looked to be from this country.
You see almost no Iraqis or Afgans. Saudi welcomes economic migrants, but refugees are kept in camps for several months, before being repatriated.
I've met a lot of teachers - a few are Jordanian or Syrian, a few are South African or even American, most are Egyptian. Apparently there's one other Brit around somewhere.
In other skilled trades - engineering and medicine mainly in this town - maybe half are Saudi nationals. If you want to see a workplace full of saudis, visit the vast but largely inert bureaucracy.
The government knows all this, and they know they can't rely on migrant work forever. They've passed a law forcing businesses to employ saudi nationals - a law which has proven easy to avoid and difficult to enforce, on account of that achingly slow and incompetent bureaucracy, and the simple lack of saudis who want the jobs.
Now the government is trying to run a kind of giant job agency, which I imagine could only work if they make registration compulsory.
At the moment, the Saudi economy is flying high, in spite of it's precarious reliance on transient and migrant labour. So what happens when it falls? The people here know the west is in recession, but have difficulty grasping that the same could happen here - or more likely, they don't want to understand that Arab capitalism isn't immune to crashes.
A recession would mean the supply of foreign workers would dry up, so there would need to be a supply of replacement native workers. Which there isn't. And isn't likely to be soon.