If you say something when you have nothing to say then, at best, you will bore people; at worst, you will annoy and alienate them.
Since they have limited attention to expend, people don't want to waste any of it on your non-statements, so you should only say something if you have something to say.
If you truly have nothing to say, then the best policy is to say nothing.
The corollary, of course, is the redeployment of some of the time and money you would have wasted by making a song and dance about nothing. A redeployment towards examining the pressing question of why your business is so uninspiring to you, let alone your potential customers, that you find yourself having nothing to say.
