Luck of the draw? difference in individuals? coincidence? I do not know but just because something does not work every time does not mean that it never works.
The problem is that after more than 15 years and many sales, all you have to show are vague testimonials from obscure sources. (not one objective proof...)
You seem to be more into black hat marketing strategies, distorting facts for your benefits, spreading vague suggestions to influence desperate infected people to buy your devices. I won't call any of these behaviors benevolent...