There is an initiative to provide children in developing world with a laptop each. Which is very laudable. What will you think if I were to tell you that enterprises too have similar initiative. They are spending money, even in these turbulent times, to put an extra desktop computer on each employee's desk?
Well that's what you do when you put a specialised VoIP phone on each desktop. A VoIP phone is nothing but a computer which runs only one application, viz. a telephone. Of course there are applications, which can run on your existing desktop PC and provide same functionality - popularly known as Soft Phones.
In fact providing soft phones to every employee, especially those on move, will make more sense. Then they can use those soft phones to connect to the world while on move, while spending only on ISP connection.
So why does not this happen? Why we keep seeing those ubiquitous VoIP phones on each desk?
I would attribute this to ineffective enterprise architecture governance. If you know how decision to introduce VoIP is made, you would understand my point. VoIP is typically introduced as upgrade to existing telephony infrastructure. Fact is, it is NOT an upgrade to existing infrastructure. If you were to replace twisted copper cable network with optical network, that would have been an upgrade to existing infrastructure. Introducing VoIP phones is same as introducing a new application in your enterprise, and hence should be subjected to same level of governance rigour to make sure it is consistent with your enterprise architecture and you understand full implications of your decision.
When you decide to use a specialised VoIP phone over soft phone, you are implicitly stating an architecture principle, 'Appliance over application'. If you chose this principle, then adding extra capability (say ability to send faxes) may require a new appliance. Whereas if you chose 'application over appliance', it might be a simple feature update to existing application. See, what I mean?
I would rather have this principle established out of an enterprise IT oracle function rather than through sales pitch of a vendor.