Why? The unknowns are mental configurations of those people who testify such claims. These are called "anomolies" and cannot be ascertained by the current understanding of the laws of NATURE. Well, these uncertainties are not addressing the origination of these anomolies, which is the human mind.
Reasonably, no science has yet confronted the human aspect of these anomolies. For millenia has humanity cleaved itself to unreasoning acclimations of thought and personal experience. The 90% "evidence" trumps the 10% validity of testifiable scientific methodology. Why?
The final approach to "anomolies" rests inside the minds of the promoters of the 90% imagined supernatural, as well as the flamboyant claims of human minds, at liberty to speak of such things.
Are the collective abstract thoughts testable and falsifiable by science? Maybe yet such an adventure shall connect the dots of human ingenuity and relative consistency of "fabled" ideas that are millenia, or even centuries old.
It finally becomes a science of mental aberration and convictions of faith and belief, both which, so far, are not testable or falsifiable. A scientific conclusion of a "don't know" is evidence of the weakness of the scientific method. How does anyone test the purely mental domain accurately and systematically?