Mage Question

[lfd]

The game labels all spells that do not have their intended effect as "resists", regardless of whether or not this is actually true.

Although you can tell the difference between a spell miss ("Resist" in white text) and a spell resist ("Resist" in yellow text). If you're seeing a lot of white resists (usually just versus Boss mobs), you need more +spell hit. Penetration won't help, and as others have said, is generally a useless stat in PvE.