Singapore's stay home notice procedures (aka arrival quarantine), a thread.
(Yes, that's a coffee cup on the ledge of my hotel room; more on this in a bit).
I think they're waiting for a long enough incubation period. Also: guaranteeing that the hotels don't go out of business seems in line with SG's 'prep for the economic recovery; save jobs' strategy; and test reagents are limited.
But not sure how sustainable in the long term.