When someone meets a friend, and the friend asks how he is, and he replies, "Not good", Hashem says, "This you call not good? I'll show you what not good is" - and all kinds of bad experiences come his way. But when his friend meets him and asks how he is, and he replies cheerfully, "Good, Baruch Hashem," even though in fact things are not good, Hashem then says, "This you call good? I'm going to show you what real good is!"
(Rebbe Nachman of Breslov)