This includes use of depth of field, bokeh effect, framing, lighting, perspective, focal length, shutter speed, focus or zoom pulling, tilt, shift, ISO, shutter speed, compositing, post-production or printing; all used to emphasise or deemphasise the subject of the photo.

Essentially, this is capturing time, timeliness, or the passage of time or the moment of something depicted.

Basically, this is the question. A good photo should always ask a question of the viewer not provide the answer. It should ask the viewer to question their own assumptions--this is what holds the viewers attention.

Think juxtaposition, the co-location of two symbols that normally go together in a manner that is ironic, absurd or manner that challenges the status quo of a stereotype.