Why must the waiters stand on the right of the host to present the dishes?

Silver service is always served from the left. But before serving, the waiters have to present the host of the party the dishes and they must stand on the right of the host. Why must they stand on the right, not on the left as they serve? Can anyone explain for me? Tks

While I'm not sure this applies to all service, typical wait staff serve from the right and clear to the left because the majority of the world is right-handed. When you are serving a course, you want the diner to notice the presentation of the dish, the colors, smells, etc. By serving on their dominant side, you grab their attention. Once the course is complete, and there is only the business of clearing dirty dishes, you don't want to get their attention, you want to do your job quickly and efficiently and not interrupt the flow of conversation - thus you clear from the non-dominant side.

on the right...you serve....on your left you clear table....so there will not be any spills or food knocked on anyone

I can not add a thing to the answer of Answer #1. It is a very concise and informative answer.