The cynical will say why don't we go about our work and just make sure we're in to receive in that five minute window between 5 to 1, and 1 o'clock, because that's when delivery men turn up in reality? But the fact is, the delivery companies don't because they hate to feel that they have wasted your time. By delivering at the far end of the spectrum, they can say it really was worth staying in that last five minutes of the five hour possibility, because if you'd waited and gone out at 5 to 1, they would have come, you would be out and you would have waited in all that time for nothing... (Continued at http://www.tinybangtheories.com/2012/03/squealing-about-deliverance.html).
Best wishes,
Paul (Ed.)