It's too easy for them to hit a few buttons and move on to your competitor's web site. If you have no regard for their time, bandwidth, and access charges, they will probably not return to your site for a second look. Graphics are important, but they should be used to decorate your pages, not dominate them. If there is a large graphic that you think your customers should see, display a thumbnail of the graphic that links to the larger, more detailed graphic. Give your customers an option, forcing them to wait may force them to leave.
Many web designers come from technical backgrounds.
They live on the bleeding edge of technology, and they are always ready to try the newest release of everything. They honestly believe that a good web site uses all of the latest features the web has to offer. But most Internet users do not keep up with the latest web technology. They do not have the time, expertise, or disk space to load all of the latest software. Simply put, if an Internet user can't display your site, you have just lost a potential customer.