The Need for Speed
http://www.useit.com/alertbox/9703a.html

Nielsen, Jakob
Alertbox
1997

Abstract:

Every Web usability study I have conducted since 1994 has shown the same thing: users beg us to speed up page downloads. In the beginning, my reaction was along the lines of 'let's just give them better design and they will behappy to wait for it.' I have since become a reformed sinner since even my skull is not thick enough to withstand consistent user pleas year after year.