Once you have the population vaccinated [1], you either make the measures permanent, or you drop them. I don't think a state of affairs is sustainable in which

Once you have the population vaccinated [1], you either make the measures permanent, or you drop them. I don't think a state of affairs is sustainable in which travel is severely restricted, borders are closed, and anytime a case flares up somewhere, the city shuts down for two weeks. So what's the criterion for an exit from Zero COVID? [1] and China is at around 90% vaccination. They might not be good vaccinations, though. But assume, for the sake of the argument, it had the population vaccinated as well as possible.