I read that mobile phones can be out by several seconds due to delays in various steps required for the data to reach your phone.
There is still a significant amount of the population without a mobile phone, much less a smart phone in their pocket who still use the service. It received plenty of calls in the last year and even people with a smart phone in certain lines of work still use it, for instance people up on ladders setting clocks who need to listen for the exact time and can't look at their mobile phone or watch.
I checked my mobile against it today and it was actually ahead by one second.
It's just an excuse by the money grubbers at "Telstra" to save $$.
