Thomas Karns:  

in rate? I always play at my best when I’m losing, and I think that’s important. Not having excuses also helps after the fact, when examining your play and your decision-making. Nobody ever learned anything by saying, ‘I got mana screwed’ (except maybe to play more land), or ‘he topdecked.’ Sometimes when he topdecked you could have won one turn earlier, if you’d made a slightly more optimal play earlier. Be self critical, but divorce your sense of self from your play. You can’t let things affect you emotionally, but at the same time you have to really examine your choices, question them, and see what you could have done better. Patrick is absolutely right when he says that sometimes you win but gave them an extra turn to kill you, or draw their out. Sometimes you wasted a card. Just because you won doesn’t mean you played optimally, so you have to be equally critical even when you win. Only by objectively observing your choices and decisions, win or lose, lucky or unlucky, will you improve, and only by not letting your mistakes rattle you will you win the next game or the next round. " -Jon Finkel".