If you call the same number 10 times in a row, or let it ring for minutes, you can be reasonably sure nobody is home. Most people would at least get pissed and pick the phone up, if only to slam it back down.
> If you call the same number 10 times in a row, or let it ring for minutes, you can be reasonably sure nobody is home.
If it has an automatic answering system, you can't "let it ring for minutes", and if it has the ringer turned off (and there are lots of people who, with an answering, do this by default) then it won't even ring at all (though you'll think it is ringing.)
