These NK operations are after salary and intelligence. The salary ensures the operation is self-sustaining even while it doesn’t yield actionable intelligence. They can keep growing their army of staffers until they get a hit on a prime target. And since nobody at the company meets the actual worker, they can rotate “employees” as needed – when a big score is in sight, they can plug their best hackers into the operation to “close the deal” (stealing cryptocurrency, trade secrets, or other actionable intel).