I used to answer my phone on the first ring, but nowadays when I’m busy I don’t even look to see who’s calling. Answering the telephone not only takes a lot of your productive time, but it also takes away from you being “in the zone”.
The best thing to do is stop answering every single call you get. Some phone calls are important, but if it can wait, let it wait. Focus and finish your task at hand, and then call back.
If you get distracted every time you hear your phone ring, then you’ll never get anything done. Its best to designate times when you call back everyone that needs calling. That way you can easily switch from work mode to phone mode, and vise versa.