Why is medusa mortal?

Medusa, one of the Gorgons in Greek mythology, is considered mortal due to her tragic backstory. Once a beautiful maiden, she was transformed into a monster by the goddess Athena as punishment for being seduced by Poseidon in her temple. This transformation granted her the ability to turn onlookers to stone, but it also sealed her fate as a mortal being, ultimately leading to her death at the hands of the hero Perseus. Thus, her mortality is tied to her curse and the consequences of divine retribution.