One of my frequent comments on advertising is that the advertising industry never produces net statistics for its outcomes; they don't measure the number of potential or actual customers put off by persistent pestering.
In response there'll be occasional replies that the industry employs statisticians who thoroughly examine results. Given that the industry doesn't seem to have spotted this one I think I'll stick with my original thought: it doesn't and daren't measure what their activities actually achieve.
Biting the hand that feeds IT
