I am the office receptionist.
Complicated telephone systems terrify me.
Fortunately, we don't use a complicated telephone system. We have three lines. No one has their own extension. When someone calls for someone other than me, I put them on hold, get up, walk over to the called-for person's desk, and hand them a phone.
It means I get to get up and walk around a good deal. I really enjoy this process. I could shout to the people who are relatively close to my desk, but its nice to split up my sitting-at-computer-time with walking-with-a-cordless-handset time.