When I was a kid, my favorite game on my GameBoy Advanced was Megaman NT Warrior. I did not see any reason to get any other game for by GameBoy as I felt Megaman was much more awesome than both Pokemon and Super Mario. The plot of this game was to switch between the real world and the virtual world and save the world from a criminal organization called WWW (World Three). WWW took over computer systems and planted viruses in the computer networks. WWW had a vision of taking over the world. I had to enter these networks and delete these viruses. In this game, the networks were a virtual world where I navigated with my net-navigator Megaman, which I used to delete viruses with by using different weapons (Activated by using battleships). Outside these networks, Megaman was on a hand-held device called PET (Personal Terminal). This powerful device would let me read emails, interact with my net-navi and contact other people.

0. No out-of-the-box framework for MVC or other frameworks for organizing your homepage

If you want to use a MVC framework or a template system, you either have to rely on a 3rd party implementation or write your own. No such thing in the PHP standard library.

1. PHP is a weak-type language

In PHP we do not care about types. If you used this variable for Foo, but you want to store an integer in it? Sure, why not? In PHP, we define the type of our variable/return-value/parameter in a comment. If you accidentally use the wrong value in a 200 lines long algorithm, PHP wouldn't even bother you that you are using the parameter value instead of a value inside a table.