Once a reasonably contagious respiratory virus begins circulating widely in a community, herd immunity can never be maintained for very long. RNA respiratory viruses (such as influenza viruses, respiratory syncytial virus (RSV), rhinoviruses, and coronaviruses) all mutate extremely fast compared to viruses like smallpox, measles, or polio. Understanding the difference between something like measles and a virus like COVID is key to understanding the con that is being perpetrated by our health institutions.
All viruses survive by creating copies of themselves. And there are always a lot of "imperfect copies" — mutations — produced by the copying process itself. Among RNA respiratory viruses these mutations stack up so quickly that there is rapid genetic drift, which continually produces new strains. Variants are normal. Variants are expected. Variants make it virtually impossible to build the impenetrable wall of long-lasting herd immunity required to starve these respiratory viruses out of existence. That's one of several reasons why flu vaccines don't provide long-lasting immunity and have to be repeated annually ― our immune system constantly needs to be updated to keep pace with the inevitable evolution of countless unnamed "variants."
This never-ending conveyor belt of mutations means that everyone's immunity to COVID was always only going to be temporary and only offer partial cross-reactive protection against future re-infections. Thus, from day one, COVID vaccination was always doomed to the same fate as the flu vaccine ― a lifelong regimen of annual booster shots to try to keep pace with "variants" for those unwilling to expose themselves to the risk of a natural infection. And the hope that by the time the vaccines (and their booster shots) roll off the production line, they won't already be out of date when confronted by the current generation of virus mutations.