The main reason for this is that ringing is there to make the caller comfortable, it is not representative of the far end phone being rung. Most people do not notice it, but it is most prevalent when calling a cellular/mobile phone. The main thing to understand is that cell phones take longer to find the users and ring the mobile phone than a land line. This can vary quite a bit from carrier to carrier. Here is what happens:
- We send the call from the Phonebooth User to the cell phone provider (carrier)
- When the carrier acknowledges to us that they have received the call, we start playing ringing to the User.
- Then the cell phone carrier has to locate their user and then send ringing to their mobile phone.
I have seen this take as long as 30 seconds. The reason we play ringing to the User from the beginning is because we do not want the User to hear silence until the mobile provider starts ringing. This is standard practice.
You need to keep this in mind when setting Find Me Follow Me setting, if you set the ring duration too short, the call may never ring on the cell phone.
Rule of thumb: do not set call duration shorter than 30 seconds to ring a cell phone.