Why three, instead of two etc etc ... ...
They have to pick some timeframe, and a quarter seems an obvious choice as its the next grade up when we talk time, minutes, days, weeks, months, quarters, years etc.
Can't understand the fuss here. Most of this legislation is being replicated across Europe. Re the video-chat; verification and recording of the conversation together with production of ID would go a long way - are you sure there is no verification of postal address e.g. perhaps via posting out time-sensitive PIN numbers?