There’s always another call waiting on the line.
Washington Times(Dec 31, 2016)
But a report by MPs says it is "not convinced" the tax authority will not repeat the "collapse" of 2014-15, when call waiting times tripled.
BBC(Dec 01, 2016)
The advent around the same time of call waiting similarly made human agency a deciding factor in whether you were available to talk.
Slate(Sep 18, 2016)