Most people look at the act, not the motivation. The US gives a lot of Medals of Honor to people who throw themselves on a grenade to save their buddies. No one says it wasn't brave because the motivation was to save their friends.

A man races into a burning house to save a child. No one says that he wasn't brave because he was trying to save a child. He ran into the house. That's enough.

Anyone who dropped on a grenade when there was no one around, or ran into a known to be empty burning house would be regarded as foolish. There is always motivation.

The person themselves may well say, "I had to do it, there was no bravery, I was frightened." The observer will still insist it was courageous.