It's a common thing to wanting to be the perfect fighter and win every battle. Yes, we can look at the scenario in a fantasy point of view, however, even in fantasy, there is imperfection. Not everyone wins, the "hero" doesn't always get the last laugh. If they did, would they be interesting in a whole?
With a character that is spot on with everything, in this case, winning, how are they interesting? What does it say about the character themselves? Yes, we could agree they are strong, but is that it? Winning does not define the character, interaction and progression does. In my opinion, if there is no loses, how can your character grow? In developing a character, it is great to see how they learn and improve themselves in whatever story-line they are put into.