They were a necessity in some places like NYC and parts of Europe, but in many other places, lockdown began before the virus spread there and the hospitals have

They were a necessity in some places like NYC and parts of Europe, but in many other places, lockdown began before the virus spread there and the hospitals have been gaping empty while lockdown continues. The original tactic was "flatten the curve" to keep cases where the healthcare system could handle them, but that tactic has been changed to "get cases down to the level where we can test & trace down to zero". Sweden appears to be the only country sticking to the original flatten the curve plan, they've been keeping their R hovering around 1, staying about 20% under ICU capacity.