Blackjack is a very mathematical-based game since players use blackjack strategy to lower the house edge and make profits. By making all of the correct moves and using good strategy, you can lower the house edge down to 0.5%. Of course, this is easier said than done because, like all forms of gambling, blackjack involves plenty of emotions too.

For example, let's say that you're making all of the correct moves, but you've still lost seven blackjack hands in a row. At this point, emotions might start clouding your judgment, and the math will go out the window. Furthermore, you could start making bigger bets than normal simply to chase your losses, which creates bankroll management problems. 

This is why blackjack psychology is so important in the game. The better you understand the psychology and emotions behind blackjack, the more likely you are to survive the rough times, keep a clear head, and continue making good moves. 

One of the best ways you can do this is by understanding the variance involved with blackjack. Each time you experience the high of winning 10 blackjack hands in a row, you will eventually lose the same amount some time down the road. Essentially, blackjack works on the law of averages where you'll go on winning and losing streaks nearly an equal amount of times. 

But the better you can keep on track and follow basic blackjack strategy during streaks, the closer you'll be to making profits with the game. Sure there are no guarantees in blackjack, but you can guarantee that you'll lose money by letting losses get to you and playing based on emotions. That said, recognize that variance happens, and keep your faith in basic blackjack strategy.