What does "load the dice" mean?

Rig the odds so there is little chance for another person to win; cheat. For example, There's no way we can win this contest; they've loaded the dice. This expression is also put as the dice are loaded, as in There's no point in trying; the dice are loaded. This expression alludes to adding weight to one side or another of dice so that they will always come up with certain numbers facing upward. [Late 1800s]