But seasonal flu vaccines don't work. Never have. Please explain.

Depends what you mean by "work." They do provide some protection, but not nearly as much as vaccines for less common diseases like hepatitis or smallpox. This is because there are many different strains of flu, they can't vaccinate for all of them at once, and they have to predict several months in advance which ones will be active. So there's a lot of error involved.

Too many errors involved. You must come up with a better explanation of what you are trying to convey. Please continue.