This is a good question. As you can imagine, no character is perfect, that is, without flaws. Odysseus is no exception. There are several instances where this is clear.
First, we can say that Odysseus was a bit lazy when he did not want to get off the island of Calypso. To be sure, he was a captive to some extent, but in the end he did not show great desire to escape. It would have been much better if he showed more effort to leave.
Second, when Odysseus kills all the suitors without remorse or mercy, this shows that that Odysseus was greedy for revenge.