Not only because of the hold Adelson has on him, but (obviously) because asking Willard what he believes is like tossing a pair of loaded dice. You usually get the same roll (win for 0.1%), but sometimes not.
Or coin flips: Heads the 0.1% wins, tails the 99.9% lose.
Or blackjack*: you will usually bust, or if you get a 10 & double down the dealer will get a 21. If you somehow get a blackjack, the dealer will too, and it will be a push or 1-1 payoff (Vegas rules).
*(for those of you with limited casino experience, playing 21 is even more of a gamble than you think. Pretty much any decent dealer can deal you any card they want you to get)