"The only time a man can be brave is when he is afraid."

I remember watching a Batman Vs Superman movie and hearing Batman say to Superman "You aren't brave... Men are brave".

What Batman meant was that since Superman is an indestructible alien there is no way that he can be brave. A being with no vulnerabilities or doubts simply cannot be brave.

I remember a similar quote from a different movie Angus (1995) which goes like this:

Grandpa: Superman isn't brave.

Angus: Did you take your pills this morning?

Grandpa: [chuckles] You don't understand. He's smart, handsome, even decent. But he's not brave. No, listen to me. Superman is indestructible, and you can't be brave if you're indestructible. It's people like you and your mother. People who are different, and can be crushed and know it. Yet they keep on going out there every time.

The people who have all the odds against them, yet put themselves out there are brave.