To me, fearless is not the absence of fear. It's not being completely unafraid. To me, fearless is having fears. Fearless is having doubts. Lots of them. To me, fearless is living in spite of those things, every single day.
The worst thing in the world that can happen to you if you're an engineer that has given your life to something is for someone to rip it off and put their name on it.