Every time an effective marketing channel is created, it's not long before we (as in marketers) ruin it by flooding it with irrelevant message after irrelevant message, until consumers finally switch off (or unsubscribe, or opt out, or ad-block). First it was Direct Mail. By inundating people with huge volumes of barely targeted and terribly written mail, we made sure that these days most people a) barely get any post at all and b) throw most of what they do get straight into