Who is pleasing whom?
God created man and the whole world with so many varieties, so many good things. God made so many types of vegetables, fragrances, flowers and thorns, dragons and horror, to please man and keep him entertained. But man got more and more depressed.
God then acted tough and man had to start pleasing Him. And so, man kept himself busy pleasing God and he became happier since he had no time to get worried or depressed. So, when you have someone to please, it keeps you on your toes and you feel happier. But if your whole aim is just to please yourself, you will get depressed. Pleasure simply brings more craving. But the problem is that we try to get contentment through pleasure. True contentment can only come through service.