Composition (content) The clock is cut off at the bottom and a lot of open space is left at the top. It is something I forget to pay attention to when framing. Busy with the exposure, avoiding camera shake and when I review it on the pc "Damn, the ship's mast runs out of the frame"..... See wingy's comment on what to do when that happens.
The black vs white is indeed very nice.
The lighting is uneven, with the main light source from the left. You could try to position a reflecting paper (A4/A5 printing paper) at the right. But that also adds a bit more light, on the other hand you have plenty of room to use a smaller aperture (higher F). Another benefit of reflecting light at the right is that it will fill the shadow in the clock at the left to some degree.
The clock seems to tick uneven, it remains in the same position for longer every two seconds it seems. :-) Well captured motion!
Background Good contrast with the clock, all focus is on the clock and the motion.
Camera Work (Technical) Excellent exposure, camera sharpness ok, dof not an issue.
Digital Processing (technical) Could have benefited from a bit unsharp mask (tried that myself). Don't forget to save your file at the highest possible quality level, it is only 50k of the 150k allowed. That might have caused the unsharp feel of "quartz", "china" and the numbers at the left side.
My opinion Nice, but not outstanding.
(edit) And before I forget to mention it, don't pay attention to comments like "we have seen that before". When I would base my votes on that, almost everyone gets a 1.
I'd either tighten the crop on top to come right to the edge of the clock, or give a little bit of space between the clock and the edge of the frame at the bottom. In fact, a closer view, perhaps only showing half or a fourth of the clock might have added to the snese of motion and overall uniqueness of the shot. I like the lighting and the white clock on black backdrop. Overall nice shot. 6
Excelent shot, great idea, and well executed. My only problem is that you cropped way too tight at the bottom. Otherwise, your angle is good, the lighting is nice, and focus and clarity are great. Motion is very clear and obvious. Great shot. Good luck in the challenge.