Can it not be like sirens singing about your deepest desires to lure you in the water. So asexuals get sung to about snuggling in a blanket with a hot cuppa of Coco.
Maybe the charm of the succubus could be the same for sexual tensions. What they find most desirable to find in others.
The warforged could see the best artificer who is able to understand all the intricacies of your function.
A monk sees a teacher who is able to gently guide their way to mastery.
Etc
How we found out? We knew from the start there would be a discrepancy. Early testing pointed to this problem. And we warned every superior up the chain. But in the end we were ordered to just put a warning on the scroll.
We were only taken serious after a junior magician thought it was funny to teleport an elephant into their observatorium before exams and neglected the warnings. That is how the Mana Void of Barkley Academy was formed.
The superiors were out for blood when the first court summon scrolls appeared, using competitors teleportation technology. That was until we gave them a copy of our manilla scroll holder full with communication of them neglecting to heed our warnings.