She turned them into swine because they behaved like pigs.
The animals in Circe's hall are Odysseus's men.
Hermes gave Odysseus an herb which protected him from her powers.
Odysseus avoided turning into a pig by using an herb given to him by the god Hermes, which protected him from the enchantment of Circe. By taking this herb, he was able to maintain his human form and resist Circe's magic.
Actually, the animals that Odysseus' men encounter outside Circe's house are not wolves and lions, but wolves and lions that resemble humans due to Circe's magic. This terrifies the men because they cannot discern whether the creatures are animals or humans.
Circe turned Scylla into a monster out of jealousy and vengeance. In Homer's "Odyssey," Scylla, a beautiful nymph, attracted the attention of the sea god Glaucus, who was in love with her. When Scylla rejected Glaucus's advances, he sought Circe's help to win her over, but instead, Circe fell in love with him. In retaliation for Scylla's rejection and to punish her, Circe transformed her into a hideous sea monster, forever cursed to terrorize sailors.
Eurylochus did not obey to the orders of Odysseus and when Odysseus brought back his colleagues from the palace of Circe they almost had a fight
Hermes gives him a plant which allows Odysseus to withstand Circe's spell and so she is not able to turn him into an animal.
Hermes, the messenger god, gives Odysseus a plant called moly (hence the fraise "holy moly"). The plant weakened Circe's spell on Odysseus. Realizing she has met her match, Circe frees Odysseus' men of their animal forms.
When Odysseus' advance party discover Circe's palace in the middle of the forest, Circe [Falcon] invites them in and gives them a meal. The men all behave disrespectfully so Circe makes the food with a magical poison, and all of the sailors are transformed into pigs, except Eurylochus - who expected a trap and has eaten nothing. Eurylochus escapes and warns Odysseus. Odysseus sets out to rescue his men, but is intercepted by Hermes. Hermes tells Odysseus that he can resist Circe's poison by using the herb Moly. Odysseus convinces Circe to release his men and then There is then quite a lot more story - but at the end Odysseus leaves with his men, and they can continue with their journey. Odysseus sent some men out and those men were turned into animals. When Odysseus tried to set them free she said she would not do it unless he lay with her.
Hermes gives him a plant which allows Odysseus to withstand Circe's spell and so she is not able to turn him into an animal.
because he knew that she was bad and wanted to turn him into an animal
Circe turned Odysseus' men Into swine.
circe sends odysseus to the underworld
There is no mention of a compass in Circe's gifts to Odysseus.
Because he ate a magical flower given by Hermes. The magical flower allows him to drink the wine but not change into an animal. That is why Circe did fail to cast the spell on Odysseus.
Hermes warned Odysseus about Circe's magic.
Circe was opening the door of her estate for Odysseus.