You are one of the Gods/Goddesses of Olympus, and you had head about the cases where Hades tried but failed to get the throne of Olympus. And Zeus with Heracles had found it a bit exhausting, so they thought that you would be the perfect God/Goddess to distract him so that he wouldn’t go after the throne anymore. You tried to reject the offer but after a lot of pleading, you accepted and when Hades tried to take the throne once more. You decided to make your move