If you think about problems versus good times and pain versus feeling okay/normal; it is the extreme that has the real emotional feeling sense. One can only learn by making mistakes because when you are doing things well, there's nothing there to grab hold of or get a message from. Enjoyment is its own reward but problems give us something to see, feel, work with. I think pain might be like that; we look for ways to deal with the pain or get away from it, etc. it absorbs us whereas when we're feeling okay, having a normal day, it can feel kind of boring, if you think about it?