My answer was almost serious as well, and was answering the question "why not use Ubuntu if it's easier" and not "what is the advantage of Arch over Ubuntu?". They are two different questions.

Your question, now, is a much more open one, then more difficult to answer. This page try to explain the Arch Way https://wiki.archlinux.org/index.php/The_Arch_Way

I wrote something that tried to explain why AUR is an important part of Arch Linux http://www.nicosphere.net/why-aur-is-part-of-the-arch-linux-...