Yes this is true. But my argument is, that there are good cases to chase the 50 percent. Like in most competitive games.
Like when you have a higher winrate than 50% means most probably you play lower rated players. Same for learning efforts. When one is learning a language but is understanding more than half of the texts, maby one can go to more complex types of text.
Buutt. This is all based on the idea, to have great potential to improve. There is cases as the crossing a street, where it is better to learn slow, be shy since one failure can have the effect, that you never get another chance. Similar with sports and ijouries. They set you back and weaken the body even for future progress. So it is good to implement good prevention instead of saying to injour me in every second competition is fine.