The clarity of your focus is very good and your exposure is good, in that it emphasises the details of the metronome with a dark background and captures some of the grain in the wood. My monitor shows a slight warm cast to this image rather than pure black and white but this could just be my settings. You have captured well the swing of the arm with a faint streak from side to side and more pronounced at the ends of the swing. Movement captured-and contrasted with the stillness of the machine. There seem to be no digital artefacts and the picture is pretty grain free.
My only quibble is the composition of your shot. I think if you are trying to be symmetrical you must be exactly symmetrical and if you are to be off centre then you must be totally off centre. Your shot confuses the viewer who doesn’t know whether it is a symmetrical shot gone wrong or what! I also feel you should have experimented with other views. Often just changing the angle to something unexpected can do wonders and invigorate the picture. You chose a straight on view that one would see normally so there are no surprises—how about from above or a very side angle—I think you should have experimented with this.
Technically it meets the challenge, I'm sure, but I'd like to see this featured in a more artistic way, perhaps a diff bg, and not quite so centered. Maybe a more creative lighting approach. There is potential here, just needs to be looked at from diff angles.
Well, I happen to know that it's a pic of a "Metranome" (spelling?), but most won't and won't understand it... You should have made the swinging arm more visible. :)