"The Subscriber cannot be reached" (Globe), "The number you are trying to call is unattended, or out of coverage area" (Smart) and if you are calling using Vodaphone in the UK (but why would you?) you will also be told that "the phone you are calling is switched off." None of these statements is necessarily true. I mention this because these less-than-always -accurate messages may have an effect on relationships. A friend who is a retired telecoms engineer pointed out to me that countries like the Philippines have their telecoms set up asymmetrically, so that they receive more calls than they make . He also pointed out that with modern digital systems there is no "end of line" handshake as such, so you cannot actually tell whether a phone was off, was not answered, or was out or range or, very often, no connection was made for some other reason - such as rain!
Correct, but try explaining the reverse situation to your partner when they are calling you and don't get an instant reply