"Courage is resistance to fear, mastery of fear, not absence of fear."--Mark Twain

To be fearless is to be foolhardy.  When you have no fear, you are lacking a vital emotional element that keeps you alive.
It's like not having the sense of touch.  When you can't feel anything, you don't know when you've been injured, and when you don't know if you've been injured, death is dead ahead.
Fear keeps you cautious.
That's not a bad thing when you're approaching a pride of lions on your safari in Africa. You stay in the jeep and listen to the guide for instructions on how to make your way safely through that circumstance.
Too little fear means you jump out of the jeep and start to play with that darling lion cub. Ouch.
Too much fear and your imagination kills your desire. You don't go on the safari in the first place. You anticipate personal injury and possible death and stop dreaming of Africa before you even buy the plane tickets.
In short, too much fear and you stop living because you're irrationally afraid of dying.
Courage is when you are afraid, but you see that the fear blocks your way to something you've always wanted; so you analyze your desire and come to a full understand of the risks and benefits.  You then make the proper preparations and take the necessary precautions to minimize the risks, realize you're up to the challenge, and you go for it.
Bon voyage.