The biggest pitfall that people find when playing Blackjack is in not being sure when to bet because they do not have a system in place. Therefore, the biggest pitfall could be said to be not having a system, but just playing by instinct. This can sometimes work, but you should really know what you are doing before you enter into a game like Blackjack. It is a very fast game that does not allow much room for error, and there can be quite a lot at stake when you are playing it either online or in a real casino. Because of the speed, you need to have a system that will tell you very quickly if you should Hit or Stand — that is, take another card or hold with only the cards that you have. This is not something that you want to leave to chance, because then you will lose more often than you win. Having a system will still allow for you to lose sometimes — for instance, if you system tells you to always hit on fourteen, you will go over on occasion. However, the system will make sure that the odds are in your favor, so you will win more often than you lose.
The problem with not having a system can be illustrated very simply. If you have cards in your hand totaling fifteen, for example, what should you do? You can hit, knowing that, out of everything else in the deck, anything over a six will put you over. This means you will certainly lose with a seven, an eight, a nine, a ten, or any face card, whether a Jack, a Queen, or a King. This means that twenty-eight of the cards in the deck will cause you to lose, not taking into account what is on the table, being held by the dealer or another player. That leaves twenty-four cards in the deck that will allow you to win. The odds, then, are in favor of your losing. Granted, if the dealer has a king up, you can reduce the amount of losing cards by one, though this still leaves it in favor of your losing the game.
This is why you need a system. You will not want to have to do all of the math in your head while playing, so you should just know that you want to Hit or to Stand as soon as you see the total. This way, you will consistently win or lose. Otherwise, you may hit sometimes and go over, while standing other times and not getting the six that would have won the game, meaning you will lose all of the time. The biggest pitfall of Blackjack is that people do not know what they are doing, and they just guess on the fly.