Why does Odysseus wish to explore the cave of the Cyclops?

He wants to see if he can get presents from the cyclops and if there is anything valuable to take

Odysseus ventures into Polyphemus' cave because his ship has stopped at the island, and he is looking for food, and hoping to find hospitality from the inhabitants (i. e ... food, shelter, a place to sleep, gifts, directions ...) But what he finds in the cave is certainly not what he expected.