I have a coworker two half-height cube walls away who will stare pointedly at me seconds before he calls out my name to molest my concentration.
I have come to find these events blood-curdling. It is simply unacceptable to me that a turned head cuts through my peripheral vision to warn me of what amounts to an assault on the mind.
The open office enshrines interruption and creates an environment whereby no moment of reflection is sacred. The neediest, most disruptive, and least productive employees are rewarded for behaving in the most antisocial ways thinkable.