First, all of us are beautiful. It follows, good images show our nice features. So, ugly photo no no for picture networks. Given, proper netiquette to make the subject of photographs look good. Then, do not post pics with bad features.
Next, great photography is recognized almost immediately with an audience. However, mediocre images may take a second look to see the beauty. Hence, an unflattering picture is one that does not put the subject in the best light.
Other examples of unflattering pictures include the subject is not smiling, does not have a shirt on, or doing something improper. These are only a few examples. There are many more types of pictures that are not flattering.
Also, depicting abuse is not flattering. Then, we want to help our friends. As a result, playful images are fun. Negative images are harmful. And so, trolling, revenge, or other frienemy photos are not appropriate. Hence, trends are not always healthy. Thus, we draw the line.
Unflattering pictures, are well, unflattering. Everyone has taken a bad picture and wishes they had smiled brighter or did something different. There are plenty of pictures on the internet that are unflattering. The internet does not need any more.
Do not upload unflattering, bad, pictures of people. It is not funny to post bad pictures in social media. Picture networks are not tabloid magazines where photographers try to make people look bad. They are domains for sharing good pictures with friends.
Coach your subjects if you have to. Get them to look their best in the picture. If a subject views your pictures online and feels that the picture is unflattering, take it down.
Ugly Photo Netiquette
It is proper netiquette to refrain from taking/posting unflattering pictures of people on the internet because it makes them look bad.