Hospitals and related services are optimized for efficiency, not flexibility. They don't like having empty beds that aren't being used, or idle workforces. So when something out of the ordinary happens they can't deal with it while maintaining their normal level of service. As a society we don't seem to want to pay for idle capacity. Human nature, I guess. We could have been building more hospitals over the last year, training more nurses, etc. But that doesn't appear to have happened.