It can bring you happiness/self-esteem. It can turn "failure" into "success." And, it can bring admiration and respect from other people.
Simply put: When you choose to look at the positive side of everything you become unstoppable. When people are complaining about this or that you will simply take everything in your stride, and happily continue being successful.
To begin with you'll have to practice this "consciously." You do that by saying: "This is good/positive because __________." Then, after you've been practicing for some time, it will start becoming automatic¾ making your life and yourself so much more happy and successful.
I hope I've communicated this message enough for you to consider choosing to be more "positive."
If you keep practicing you will see that everything I've told you (and much more) is true. : )