Email is becoming less reliable
In a recent test, 40% of emails were not received!! Fred Langa (www.langa.com⁄about_fred.htm) did a very interesting study. He requested help from his readers to test the reliability of email. What he wanted to find out was how frequently emails sent by someone with an unfamiliar email address would fail to get through. Over 10,000 readers responded and he cut the list off at that point. I got a nice email from him saying I was too late as 10,000 was as many as he could handle (this took all of 2 days).
He sent those 10,000 an email from "Liam" - a fictitious person. They were sent individually with a message designed to look like personal email, not spam. They were sent individually, not by bulk email. He was trying to find out whether a personal email from someone you didn't recognize who wasn't in your address book would make it to you. This could happen if a friend got a new email address or suggested someone write you. He requested a response. Only 60% responded. 40% got lost. Remember they were expecting his email (though not from that name), and had agreed to help.
The point is that people are being so overwhelmed with spam, that they are loosing a lot of their desired email, making email an unreliable messaging system.