Bad beat

In poker, bad beat is a subjective term for a hand in which a player with what appear to be strong cards nevertheless loses. It most often occurs where one player bets the clearly stronger hand and their opponent makes a poor call that eventually "sucks out" and wins. There is no consensus among poker players as to what exactly constitutes a bad beat and often players will disagree about whether a particular hand was a bad beat. A few examples are: quads over full house, quads over quads, straight flush over quads, small full house vs. bigger full house or better.

Any hand that looked like a favorite to win can end up losing as more cards are dealt (with the nuts being the exception), but bad beats usually involve one of two not mutually exclusive scenarios:

A bad beat can be a profound psychological blow, and can easily lead to a player going on tilt. Professional player Phil Hellmuth, among others, is notorious for his pronounced reactions to bad beats. However, suffering a bad beat means that the losing player was "getting the money in good" and in most instances would win by playing the same hand the same way. Thus, the more stoic poker players accept bad beats as an unpleasant but necessary drawback to a tactic that works the vast majority of the time.

In online poker rooms, bad beats often lead to accusations that the random number generator is "rigged", even though such beats also occur in offline games. Many online poker rooms post statistical data to demonstrate the randomness of the hands generated. In online poker games players have an opportunity to play in "bad beat" tables where the player who has the best losing hand receives an accumulated prize pool. An additional amount of rake is taken from each hand to fund the jackpot. The largest online jackpot to date was €1.25 million, hit in July 2011 with €443,000 going to the loser of the hand.

Players are statistically more likely to experience bad beats online, since playing using a computer allows for more hands played per hour. Also, online players may play multiple cash game tables and/or tournaments at the same time, also increasing the frequency of hands dealt. Also, tells are rendered moot, so players are incapable of reading clues such as body language in aid of deriving the strength of an opponent's hand. Finally, online poker games (especially freeroll tournaments)are far more accessible to the average player who, being average, is less likely to be knowledgeable regarding the techniques of the game, in turn making it more likely they will bet from the gut or intuition rather than experience.

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Wikipedia