how can a sweet dish make life interesting?

Actually there is no hard and fast rule that we should have a sweet dish at the end of the meal.It gives us a pleasant feeling and a satisfaction of a full meal.

I think that by finishing your meal occasionally with a desert serves as a sort of reward for us. It can be a reward for almost everything, from a job well done to even eating something that you don't enjoy. But regardless, I think of it as a reward. That said, I think that the reason that enjoying desert from time to time makes us enjoy our lives more because it shows us that there is something to look forward to at the end that is a very pleasant experience.