As a system of communication email works best in the two way mode. The one way, or “unidirectional” mode can lead to the sender being left without sufficient feedback on which to base their understanding of the manner in which the email has been received.
Essentially this is the online version of telephone heavy breathing. Its wide open to interpretation/misinterpretation and can lead to stress and tension as the sender wonders what the reception, more pointedly, the lack of reception actually means. Did it get there, was it dropped in the spam box, did I send it to the wrong person, have I been black listed for some unknown offence, am I one email away from a restraining order, is the recipient in hospital, dead or simply suffering from a serious blow to the head from a disgruntled cow and is now living in Honduras selling cheap necklaces and thinking their name is actually Miguel/Miguela?
The actual answer, 99.95% of the time is actually a serious case of couldn’t be arsed responding on the part of the recipient. But this is of no comfort to the poor sender who is now near paralytic with wild imaginings. Should I get a lawyer/forensic technician, what will I wear to a funeral, is it ok eat the grapes if the person you are visiting in hospital is actually in a coma, how much will a snatch squad of former SAS troopers cost to carry out the rescue of a memory impaired individual and does reprogramming really work anyway?
So in short while not replying to emails may be good for flights of fancy and works of extreme fiction it is actually a very poor option as a communication system. A one way email is in fact just a form of pasive advertising and not very good value for money at all. So be kind to the terminally imaginative and reply to your emails.