In sports, there is always someone winning dominantly. It can get to a point where they are almost always expected to win. By that point do you continue to bet on those favorites to keep winning or does it bore you? Would you enjoy stirring it up a bit just for the fun of it and betting on the underdogs even if the chances are quite low?
It's normal for me to bet on a team with a high chance of winning rather than taking a big risk on a team with a low chance, even if they lose, which is common in gambling. Nothing is certain in any sport or game; even teams with a high chance of winning can lose, as in PSG's defeat to Chelsea. I didn't want to take a big risk on Chelsea because PSG was so convincing, but sometimes our expectations never match reality.
PSG's defeat yesterday left many bettors who had backed them devastated, but this should be accepted as a normal part of gambling, preventing us from feeling deeply disappointed. Hoping for a win is certainly fine, but it shouldn't make us forget the risks or possibility of losing.