RxJS combineAll Operator, explanation

Question

I\'m trying to understand how does the combineAll operator work. I\'m using the following example from the official documentation:

Answer 1

Consider that combineAll:

flattens an Observable-of-Observables by applying combineLatest when the Observable-of-Observables completes.

And that combineLatest;

will actually wait for all input Observables to emit at least once.

So the first emission from the combineAll observable that includes the first value of the "Inner 1" observable is not going to happen until the "Inner 2" observable emits its first value. So there will only be nine emissions - not ten.