Mistakes are part of humanity  and it is unavoidable. Sometimes when you experience mistakes, you come out better. Every negative experience is either to make or mar you. For some,  it is an avenue for making amends and for some others, it is the same mistakes over and over again thereby  making them fools. What I understand by experience being the best teacher is that  you got it wrong the first time and you are taking steps to make sure it didn't repeat itself. A woman who divorces her husband on grounds of infidelity alone has made a mistake and if she is to get married the second time, she should learn how to  see things in reality ,wiser  knowing that most  men will cheat and then  concentrating on his strong points or make the same mistake of divorcing him and being called a fool. So experiences are meant to make us better persons , more perceptive and more open to constructive criticisms.  My 2cents though.