Because Drupal is extremely flexible. The Modular System to build sites works really good. And i like clean HTML Code, and with Drupal you could nearly change every code snipped the user gets.
This Site is a site for a small entrance doors dealer. The user could change the order of the nodes on the most pages with drag & drop. For the slideshow I use the Royalslider, for the implementation of the slider I wrote a little helper module. The site is build up on a complete now theme which is responsive.
There are 3 little modules i developed for this project, but they are currently not contributed because they need some work before. One module creates a single page to clear the cache, so i have a single permission to clear the cache.
Another module integrate icons to drupal, for example to the local tasks.
And the Royalslider module.