Natural Career Progression Question.

I've recently gotten more interested in MotoGP and was curious what the natural career progression was. More specifically those who start/race in the Redbull Rookie Cup. Do they typically move from there to Moto2, then Moto3, then to MotoGP? or does Moto3 come first, then Moto2?

I've recently gotten more interested in MotoGP and was curious what the natural career progression was. More specifically those who start/race in the Redbull Rookie Cup. Do they typically move from there to Moto2, then Moto3, then to MotoGP? or does Moto3 come first, then Moto2? http://ifttt.com/images/no_image_card.png