I have taken part in Professional Photographers of America's International Print Competition for the last few years. Print Competition is one the things that greatly improved my photography.
Creating an image which evokes emotion.
The quality of the image from the technical standpoint. These can include retouching, sharpness, exposure, and printing.
The image is unique and shows imagination.
This can be done in different ways, such as a specific lighting, composition, or other idea that the artist brings into the image.
How you choose to place elements into the image. How your light is falling, what is in foreground and background, framing, all of these go in to composition.
How you are showing your image. Images are not just shown like you would see them online. They are matted and framed in unique ways to help tell the story.
The colors work together with the image to create a feeling.
Your eye is drawn into the intended subject.
The artist demonstrates excellence in the use and control of light to help tell the story.
An uninteresting subject can be made interesting with use of things like composition and lighting. It doesn't have to actually be interesting in real life, just in your image.
What you do to create your image with lighting, presentation, etc.
The image bring a feeling to the viewer.