Hopefully I have chosen the correct forum for my question.

:
No matter how good or bad the design is on a business site, the final determining factor of success is if the product or service sells.
My question involves understanding what makes the public choose to buy or choose not to buy from a site?
I would love to see examples from various sites used in the answers so all of us can truly understand and develop our sites accordingly.
If you were looking at either of our main sites... What would encourage you to make a purchase? What would make you nervous about making a purchase?
http://www.gnc-web-creations.com
http://www.mississippi-photo-gallery.com