Try to take a really good watch photo. Try to take a watch photo as good as these. Just try to take a watch photo with no unwanted reflections...of the camera...of the surrounding room. After you get to that point try to place the highlights and shadows in the exact places where they show off the watch...make it look 3d in the 2d world of the screen or the print. Try to get the colors right. Try to make a watch photo with no flaws like the watch photos these guys make and it will be easy to see why it can take them so long. It will be easy to see why because quite frankly, most of us won't be able to do it...in a full working day or ever.
JohnCote