What value is there is requesting comments and critiques? It's all just personal, isn't it?
It is a feature of "good art" (whatever that is, let us agree that our ideas of "good art" overlap sufficiently for rough work, here) that it is not only evocative, but that it tends to evoke similar reactions from many people. If your goal as a photographer is to make "good art" then, surely, you want to produce photographs that evoke, and that evoke similar responses from "most" people.
Having colleagues, friends, classmates, or random people on the internet "critique" your work, then, is a bit like a poll. You ask, really, do you react to my photograph? If so, tell me about your reaction, please? Then you gather up the answers, and see if they seem to cohere. If they do, then your photograph communicates in a coherent fashion. It might still not be good art, but it has one of the features of good art. If almost nobody reacts to your piece, you know it's probably not good. If people react, but the responses are all over the place, your work is apparently something odd -- it evokes, but not in a coherent way. All these possibilities are interesting and informative to the artist.
This is science: If you seek to communicate, you should attempt to communicate. "Test, test, 1, 2, 3, do you read? Do you read? Over." If the attempt fails, you should seek to understand why, so you can do better the next time.
When selecting people to critique, it's important to rule out certain groups, I find. Most internet forums are filled with technical nerds, who will tell you all about how your focus is wrong, and how you ought to follow the rule of thirds, and that your white balance is off. These technical details are largely irrelevant. They matter only to the extent that they color a viewer's response to the image. It's also important to rule out excessively studied critics. The last thing anybody needs is a rambling lecture on Postmodernism, or similar.
The useful responses are simply a record of the viewer's reaction, perhaps with some detail and a modest effort to understand the reasons for the viewer reaction, if any can be discerned. "Yes, I read you. Two by three."