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?
This unbeaten pattern do happen regular in the hose leagues which are referred to as farmer's league because one or two dominant teams dominate the league with high winning chances than any opponent they meet. I think we all know that such situations are usually boring because it's like we all know the ending of the game's result from the beginning before the end. Something about those clubs in such leagues, their odds are very low that you can't make a good profit from picking them.