I started working for a furniture manufacturer, many years ago, as a design engineer and their IT person. When I got there, they had a switchboard operator (receptionist) who did the typical handling of all incoming calls then transferred them to the appropriate office with a two digit extension. About a year later, the company "upgraded" the phone system and everyone then had three digit extensions, no new offices. They just added a number to the front so everyone had to add a '9' or something to their regular number. Then they upgraded again to a trunk line where everyone got their own direct dial number and internally, they now had four digits to dial to get a fellow employee. Progress?
I've since left the company, but my guess is that, another upgrade and all seven digits now needs to be dialed to get the office that twenty five years ago only took two numbers to dial. Oh yeah, they still maintain a front end receptionist to handle phone calls.
-Will (Dragonfly)