A professional presentation does not mean a slick presentation

Seth Godin picked a T-shirt print provider based on a clean and professional looking web site and a straightforward pricing policy because it conveyed a sense of trust. There are lessons for presentation designers here.
It is good to invest in your presentation design. Over-doing the graphics though might give a negative return on investment:
  • Highly complicated and sophisticated slide backgrounds
  • Big graphical elements in the template, repeating on every page, leaving no space for the actual chart
  • Drop shadows, bevels, glows, gradient fills, and reflections galore
  • Professional, highly detailed, illustrations exported from Illustrator into PowerPoint
  • Spectacular animations and slide transitions
  • Beautiful, but too obvious/cheesy stock images
We can all imagine a slick sales person (cars, kitchens, insurance). Do we trust them?