My favorite explanation of this phenomenon, beyond the visual demonstration, is that lag time reminds the human mind that it is interfacing with a machine. Bec

My favorite explanation of this phenomenon, beyond the visual demonstration, is that lag time reminds the human mind that it is interfacing with a machine. Because that feels unnatural, it creates fatigue and builds separation between the user and his work. UI guru Jakob Nielsen has an excellent description of this here: http://www.useit.com/papers/responsetime.html http://www.useit.com/papers/responsetime.html