Burning out so fast.

[Naria]

There is that, but encounters themselves become more complex. Positioning, timing of abilities and situational awareness are all factors that increase importance the higher in level you go. At the the beginning of the game combat isn't much more than target this and mash DPS buttons. The higher you go the more likely that behavior will get you (and possibly everyone in your party) killed. The game very slowly eases you into more complex combat, but combat in a lvl 60 raid has little resemblance to Satasha.