Mainly because I am a textual/visual communicator. I really dislike speaking to people on the phone.
Just the opposite here. Can't stand texting. So you start to see the reasons for my numbers.
As a side note, I hadn't considered rollover minutes. I don't have those now so it never entered my thoughts. I guess I should re-analyze my last 12 months of use and see if some months were lighter than others. If so, rollover minutes might make a difference.
Probably not, but worth checking!