system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Wars] Why is Cassian Andor, a Rebel Intelligence officer, such a bad liar?

In the novel they even imply he's been undercover at some time, as he knew exactly how to wear an Imperial Officer uniform. But he clearly gets nervous when he heads to assassinate Galen and Jyn wants to go with him, and then again when Jyn confronts him about wanting to kill her father.
gpt
Everything he has done so far, has been on his moral beliefs of being for the greater good.

Assasinating Galen put him in a dilema, as he sees it could however harm the greater good, but he had orders.

Throw in someone bringing the human out of him, he was experiencing a Personal Crisis.