…in an information-rich world, the wealth of information means a dearth of something else: a scarcity of whatever it is that information consumes. What information consumes is rather obvious: it consumes the attention of its recipients. Hence a wealth of information creates a poverty of attention and a need to allocate that attention efficiently among the overabundance of information sources that might consume it.
Herbert Simon, Designing Organizations For An Information-Rich World, 1971
I actually disagree with the premises of Attention Economics (see The False Question Of Attention Economics), but I am pulling this quote out so I can cite it easily. Davenport and Beck’s 2001 The Attention Economy solidified this concept in popular discourse.