Mailing the story:

There's no dearth of Linux distributions to choose from. With so many to choose from, one might think it's as easy as picking up the Linux kernel, throwing in a few applications, setting up respositories, making ISOs and you've got a shiny new Linux distro. Well, there's more to a Linux distro than assembling applications and making sure everything works. A lot of time and effort, at least for major distros, is spent on making the distribution secure and getting updates out in a timely fashion.