The Elemental Hero Lady effect states: "You can Special Summon this card from your hand by removing from play 1 "Elemental HERO" monster from your Graveyard."
The effect does not include herself.
This is because the effect requires you to remove from play a different "Elemental HERO" monster from your Graveyard. Lady herself does not qualify, as she's the card you're trying to Special Summon.