In blackjack, players often exhibit various biases and heuristics that can influence their decision-making. One common bias is the gambler's fallacy, where individuals mistakenly believe that past outcomes affect future events, leading them to make poor decisions, such as assuming that a winning streak will end or that a losing streak will turn around. Confirmation bias also plays a role, as players may focus on results that support their beliefs about strategies, ignoring contrary evidence or outcomes.