What all the measures hope to achieve is to prevent the healthcare services being overwhelmed by the rate of infections. So policy is either suppress or mitigate.
The policy of common-sense precautions (wash your hands), social distancing (reduce contact) and isolation (reduce cross-infection) hopefully slows the rate of infection which gives healthcare a fighting chance. The more people ignore these guidelines, the more stress they put on the system, even if they themselves are not infected, they might unwittingly infect others.
As the healthcare system becomes overloaded, there are deaths not only from those in the 'at risk' bracket, but those in the system for other reasons, not associated with the virus, who suffer because the system is overstretched, and they die, where previously they might have been treated in time. Then we have the workers themselves who are over-stretched, exhausted, and thus their resistance crumbles, and they start dying, too.
Because people ignore the basic precautions.
I find myself in the 'at risk' camp because I'm over 60 and I've just been identified as having an aneurysm. This was a chance discovered in a voluntary 'lung check' programme looking for early symptoms of cancer (all clear). Having just been referred by my GP to a cardiac specialist, I now hear that all 'routine' exams are on hold to cope with the influx of virus cases. So my appointment, diagnosis and treatment is deferred, and we (me, family, GP) do not know how serious, or not, the condition is. (GP: "In the meantime, should you get a stabbing pain in your chest, dial emergency.")
Scary enough at the best of times, but when I hear that Italy is now no longer intubating the over 60s because they're preserving resources for the below-60s.
The refusal to take precautions is a classic "Am I my brother's keeper?" complaint, because if we truly loved our neighbour, we'd do everything in our power to ease us all through this crisis.