The common claim is that the quality of traditional telephony is sufficient for the application and that every other solution offering more quality is probably just a marketing ploy. Imagine this situation:
Someone from tech support finally called our office via phone for the device in the server room that was beeping really loud. The caller said he couldn't hear anything beeping on his end. The device is quiet again, but how can this be? Some hotlines play music when they put you on hold, so this is hard to believe.
This happened to me and I was the one who called the office to analyse whats going on with the UPS that showed up in our monitoring.