I am positing this while at the same time being aware that I am not entirely certain I know what the question I should be asking reallyis, so I hope you will forgive some meandering and confusion on my part.

I've been reading The Quantum Universe by Brian Cox and Jeff Forshaw in an attempt at finally coming to some degree of understanding as to what quantum mechanics actually imply and finally worked my way to a point where they've started mentioning the idea of multiple interpretations, notably the Many-worlds interpretation.

To my understanding, the reason it is brought up is that if we attempt to measure the entirety of a system it is necessary that we look at previous events as well, and the possibility that we must look into both what we observed happened and even possibly what could have happened but didn't to end up with the correct result.

The problem I'm having is that I'm not quite succeeding at grasping where exactly this kind of interpretation becomes necessary - the closest idea I can picture is essentially the throwing of two six-sided dice where the probability of a certain outcome for each dice is going to be 1/6 no matter what, even though the probability of a certain result including both dice has a separate probability distribution. Since you can view this situation both per dice and with both dice at once (and each one is, to my understanding, equally correct depending on what observations you are making), I'm not seeing where exactly the interpretation issue becomes necessary.

Of course, I realise that what I am essentially doing is trying to intuitively understand something that - as far as the book is concerned - can not be intuitively understood (only believed to be understood by failing to understand the actual complexity) so I full well expect I might get an answer that basically boils down to"It just is the way it is and it doesn't care whether you get it or not."