If you send a single email to each person on your list and don't email them again unless they request more information or signup to your news list, then I don't

If you send a single email to each person on your list and don't email them again unless they request more information or signup to your news list, then I don't think it matters how big your list is, the only question that comes to mind is if your list is too big, it reduces the odds that its well targeted? I guess it depends who the target market are, and how big it is. In my business id probably hand pick the companies on my list.