After Yom Kippur we must only make the Beracha of Boei Meorei Ha`Aish on a fire that was burning on Yom Kippur.
This is because the Brocha on Motzai Yom Kippur is for the purpose of giving the message that Yom Kippur is holier than other Yomim Tovim.
Since we only use a fire that was used on Yom Kippur (not lit or cooked on Yom Kippur), it should remind us that while on a regular Yom Tov we can light fires and use them to cook, on Yom Kippur we may not – because Yom Kippur is holier.