Yet Another tale records that a demon named Madan acquired Vak-siddhi, by which whichever he mentioned came real. He misused it to trouble people and murder men and women. Another etymology indicates that valga implies "to paralyze" and symbolizes the strength of stambhana, "paralysis" that the goddess is claimed to grant; this theory https://www.youtube.com/shorts/5VeSyP9JRw0