This statement does make sense in the realm of audio processing. Moving from analog to TDM Digital, to Packetized Digital audio does add latency. Compare an analog radio (either two way or broadcast) without any digital signal processing, with a analog one with signal processing, to a digital one - each step in there, the latency goes longer.
On a full duplex phone call, you can tolerate quite a bit of latency, upwards of 600ms, provided there is no echo, as soon as echo is present, we notice the latency - but even on echo free calls, the longer the latency, the more likely both parties will end up speaking at the same time.
On a full duplex phone call, you can tolerate quite a bit of latency, upwards of 600ms, provided there is no echo, as soon as echo is present, we notice the latency - but even on echo free calls, the longer the latency, the more likely both parties will end up speaking at the same time.