Just like when you wear too much jewellery, when you wear a piece of jewellery which is too big, let’s say it is a watch, you will draw a lot of attention to it. And when I mean attention, I don’t mean it is a good attention.
Having a big a watch will make you look unfashionable. Having a very long necklace could be worse. It will make you look more feminine. If you want to image to be that way, then you ignore my warning. However, if you want to build up a manly image, you should avoid wearing big watch or a very long necklace.