Article from VoIP_News
#1 – No change in the basic user experience
If your employees are rooted in the pre-Internet world, they’ve been using desk phones for a long time, and probably the same one for most of it. In fact, it’s not uncommon for the desk phone to be the longest-serving tool in use for communication or getting work done. Perhaps the fax machine has been there longer, but there’s probably just one of those in the office. In terms of what’s on the desk, PCs turn over every few years, but desk phones last pretty much forever. Many employees are using their mobile phones more than anything on their desk, but these turn over even faster than PCs.
Your desk phones likely have a very high level of familiarity, and even though they’re all identical, each employee has a personal attachment to “their” phone. Unless it’s broken down or becomes a hazard to use, they won’t see a reason to change. If their job entails a lot of phone usage, it will be important to know that the basic user experience will stay the same when VoIP comes.