Navratri - Day 9: Siddhidatri
It's also significant that this is the culmination of the Navratri of the nine days and it's on the 9th day. So it is a sort of accomplishment for the devotees also who have been praying and sometimes even fasting and observing some particular rituals and some rules and regulations to be followed on these particular days. And the 9th day marks the culmination of all that. In a manner of speaking, the devotees have also achieved something by the time they reach the 9th day