Yes, you must know when to end the game in a winning or losing situation. You will understand it if you observe carefully when you are winning and the profits stop rising, they go up and down at a level and if you insist you will lose more of your profits, this is the point where you must leave. When you are losing you will see small profits that cannot reverse your total loses and if you insist there, these small profits will vanish and you will have only loses, and there you must end the game. Knowing when to leave the game is a great satisfaction, like when you are winning!