It's not essential to have 100% coverage, just like it's not essential (or feasible) to have 100% compliance with lockdowns. The one thing this is missing (IMO

It's not essential to have 100% coverage, just like it's not essential (or feasible) to have 100% compliance with lockdowns. The one thing this is missing (IMO) is targeted quarantine, which we've seen in Korea, Taiwan, Hong Kong and Singapore. There will always be clusters that escape surveillance, so you target specific quarantine and "lockdown" tactics, dynamically, to the smallest effective region. In the case of South Korea, they've gone as far as isolating particular buildings for lockdown.