If you played Diablo 3 already (and you probably did, like the rest of the world), you probably saw that you are forced to select one skill from each of the skill tree categories (Defense, Primary and so on). However, this is not entirely true! You are not forced to do this and you can easily unlock complete customization of the skill tree in Diablo 3 without cheating or hacking – it’s a feature of the game. It’s just that the game itself does not directly tell you about it.
As a wiz having arcane armor and magic weapon is a pretty friggen huge option to hide.
It was pretty much the most posted tip on day 1 on every website on the internet. So, I can't really answer the question as to how you didn't know about it.
Why am I homeless? Why do all you motherfuckers need homes is the real question. They called it The Prayer, its answer was law Mommy come back 'cause the water's all gone