In the book 'Dark Matter' by Blake Crouch, the central plot theme is a 'box' that creates quantum superposition (see Schródinger's cat) such that, every time you make a decision, an alternative universe branches off from the one you are in. As we constantly make decisions, the alternative universes (multiverse) that are created are infinite.
In the book, many versions of 'Jason' are created by the 'original' Jason in his trips through the box. However, there is only one version of Jason2 who originally kidnapped Jason1 and started the whole ball in motion.
Shouldn't the 'final' universe they end up in be completely awash with an infinite amount of Jasons and Jason2s? After all, Jason2 made choices all the way through, yet we only ever meet one of him.
I realise that infinite numbers of protagonists in a story will be a) confusing & b) difficult to write but I was wondering if there was a scientific reason for this?