Photographic Beauty is different than the "normal" beauty aspect per say, it is more of the texture, pieces, and introduction to the photograph. It's something that may be hard to catch with words, or even something the world is sheltered from, and doesn't want to see. Beauty can be seen when there is a story without words.
When people think of "ugly" I believe they picture something they wouldn't want to just sit and look at. Images of war, death, and pain can be very intense and moving and yes even beautiful. Images of insects, spiders especially can be gross or scary but as an image beautiful and unique. Even images of say scat, if you get close enough and an interesting angle that makes you focus on things other than what the image contains can end up being a beautiful picture.
An image of a scarred face, not the prettiest face, but the message of the Afghan women who are marked by their way of life, the boldness of the scar and the color of life surrounding it. It's a beautiful image in its own way.