Liao Chaidian, president of American International Investment Consulting Corporation, has a law of percentage. If you meet 10 customers and only get a 200 yuan order from the 10th customer, what do you think of the first 9 failures and rejections? He said: "You The reason why you get a 200 yuan order is that you get 10 customers. It is not the 10th customer that gave you 200 yuan, but it should be considered that each customer made you 200  10 = 20. Yuan business. Therefore, each time the income is rejected is 20 yuan. When you are rejected, thinking that this customer rejected me, it is equivalent to me earning 20 yuan, should also smile, salute, as income 20 yuan. ". What does this text emphasize? ['Failure is part of success.', 'When you fall on the way forward, you should stand up with a smile.', 'In life, success is not the last success.', 'When you know how to treat failures correctly, every failure has value.']