G and Random?

[Kanger]

I am sure other brighter minds have given this more thought than I have, but it seems to me that the G series is a legitimate lettered series just like V or M. Yet here we also have the random series, a mixture of numbers and letters that seem to have no pattern. Having said that, I personally believe Rolex production is EXCEEDING 1 million and the G serial, where each watch is assigned a number from 000001 to 999999, simply cannot match production, therefore we have a random serial to accompany the G. What are your thoughts on this topic? Thanks.