Actually in this case my opinion will be that overconfidence is never be good for anyone. I have also lost my bets many time for only my overconfidence on that match. And it is obviously a foolish work if anyone stake all put of our confidence in any club. But here we may also be wrong that what we think is over confidence may not be over confidence because people place their bets from a prediction of their own.
It is good when we check our decisions because we don't always make a better decision always. Whw we recheck our confidence about a particular game or bet can help us reduce loses that could keep coming when we don't test and recheck every decisions we take. I am seen many people bragging about there club of winning a particular match when it was obvious that such a win was gonna be difficult or the result is never certain. Emotions is one of the things that had been making us to keep being confident about our decisions even when we know that we could fail or lose. We need to always check and see if what we are having confidence about us going to fail us or not.