As a VoIP customer, I can attest that the number one factor that affects quality is network quality. Without an adequate pipe to route traffic, internet telephone (VoIP) calls sound terrible.
According to The Register, potential VoIP business customers in the UK are avoiding the technologies because their internet connections to branch offices aren’t good enough to support VoIP network traffic.
Many of these business use ADSL as their link to the outside world and some research shows that many potential customers don’t think their network connections can handle the traffic. According to the survey mentioned in the Reg article, 54% of customers haven’t converted to VoIP for voice calling and 70% of these respondents do so because of ‘unreliable voice quality’.
If the network traffic troubles would subside, 90% of repondents would jump at the chance to go VoIP, in order to save calls.
If telcos would provide adequate Quality of Service or traffic prioritization, VoIP quality would increase and therefore, so would VoIP business.