Why does jabba the hutt want to strip Princes leia naked?

Answer 1

Leia was put into a collar because Jabba wanted to keep her as one of his girls, after she tried to free Han Solo, whom Jabba had frozen into carbonate after he failed to pay Jabba the money he owed him.

Answer 2

It doesn't necessarily show that he wanted to do this, but you're right it wouldn't be a surprise given what was implied that he wanted to and probably had done to his previous slave girl.