As the name literally means, goddess Siddhidatri is the giver of siddhis and success by fulfilling all the wishes of the devotees.According to scriptures, Lord Shiva also attained all the siddhisby worshiping this Goddess. They both together as Ardhanarishwara created the 14 spiritual planes of existence and all living and non-living creation.
This day marks the end of rituals by finishing Durgasaptashati recitations or other chanting and performing visarjana. At places, kanyapoojan is observed on this day instead of on 8thnavratri. Devotees get their wishes fulfilled along with enhancement of their various skills and powers. Person must ensure the righteous use of it in favour of the creation created by Goddess.
Goddess Siddhidatri is worshipped by following mantras-
Om Devi Siddhidatryainamah