In reply to Peter Cralen.

Why people put slider on web site? The reason is that WordPress has evolved from a pure blogging platform to a full-blown CMS, and people make business out of it. In my area, there are several graphic design companies started to use WP to design web sites for other companies and they don't need programming skills and they solely rely on plugins and themes to design web sites. When this kind things happened, they don't have knowledge to act upon.