I'll give you a longer drawn out answer-
When it comes to trading, one of the things that new traders have to do is learn to accept that there will be losses. Most traders start out looking for some sort of 'sure thing' even if only on a subconcious level. A holy grail.
What traders eventually learn is that a very big percentage of their trades will be losers. It will be close to half of their trades, so that is something one must learn to accept- half of your trades will lose money.
What makes traders successful is that they follow a money management system that limits how much they will lose on each trade. They do this because they know that there will be times that many trades in a row lose and they want to limit their loses.
This is truely the key- small losses so your account never suffers.
One uses a stop to limit their losses to a certain percentage of their account. For most, this percentage is 2%. By ensuring that they never lose more than 2% on any trade, they are 'keeping themselves in the game' through the tough times.