The quality of VoIP highly depends on the economy of bandwidth needed to transport the packets.
That is to say "Less is More".
The first move in any creative process is to introduce constraints.
This brings potentials into focus which may be overlooked in more generous conditions.
A "smart director of the Internet Revolution" could say:
"All I need to make a movie is a computer, a room, a man and a (pretty) girl."
Of course you also need some brain.
The goal for every Net content is "Shrinking".
The smallest the packages, the biggest the audience.
And in the case of VoIP:
"VoIP is limitation, the essence of every call is compression."