We always try to find those tools that make our life easier as administrators. I personally dislike tools like
phpmyadmin but I bet there are a whole lot of people out there who just find it more comfortable to edit their databases with it and not just that. Running a web hosting company is really a whole lot of headache. Managing users could be somewhat problematic and require customization and fine-tuning of services on the system.
Some tools are out there to make the job easier, the guys from the debian community decided to make our lives easier and keep a list of these tools online: http://wiki.debian.org/HostingControlPanels