Critiquing one another s work often gives you a perspective on your own photography that you might not have considered before. As photographers, we often get so invested in what we re doing that we fail to see some small things that can make a photo better. If another person can point this out to us, it can lead to some improvements in our work.
Be prepared to receive advice that you don't like, or don't agree with. If you receive what you think is bad comment, first think about the comment from their point of view. They may well just have a point. However, if you still don't agree, be polite and respectful or better don't reply. Never get into an arguing match with someone who doesn't share your opinion of your photo. It is, after all, only an opinion and everyone is entitled to their own.