To call your client stupid is a self-fulfilling prophesy. After all, they hired you.
Your clients don’t know as much about design and technology as you do. Some may be completely befuddled. The disparity between what you know and what they know will always exist. Instead of looking at this gap as a comical gulf of ignorance, view it as a reminder of why your services are valuable to them. Then consider how valuable they are to you. If you’re in the business of selling design or development services, you need clients. The checks they write pay your salary so you can afford cool typefaces, legal copies of Adobe software, and oh yeah…things like food, utilities and shelter. It’s on their behalf that we’re commissioned to architect the digital world.