Poker steels a person to handle the unexpected.
Those who’ve played the game even for a short while -- and who’ve paid attention enough to absorb some of the odds and probabilities -- become accustomed to surprises. You know, kings cracking aces, the occasional one- or two-outer showing up on the river, or various runner-runner revelations that can make improbable winners of all-but-certain losers.
Of course, even with such knowledge, we still experience a certain level of surprise when such things happen. If we’re human, that is. Experiencing such emotion is part of what helps keep the game interesting to a lot of us.