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?
Winning in gambling doesn't get bored anyone, evening if you continue playing the same game every day, as long as you are not super rich and you continue to win always, you will never get bored of winning. Even if you want stirring up a little and you tried and lose, you will quickly go back to you place of winning. How ever, winning in gambling can not be dominant, everyday is not the same, you don't get to be lucky every time no matter the amount of effort you put.