Being positive doesn't mean that you leave the way of criticism. But criticize in respective manners to bring something more betterment in, along with appreciation of the work which has been done by someone. But generally it is not done. We begin to criticize someone in jealousy with negativity, because we don't have ability to do that. And this the case with every loser. To create something new is not an easy job. But to comment and criticize is a fun by which we can easily divert the people from the task and play our game. I often use to say that when we face a mirror to make up ourselves, we should set it at 180 degree angle. Only this way we will be able to correct ourselves. But if mirror goes out of its angle, we will begin to criticize others. Because our face disapears from mirror, we view other ones face and start cricising him.