RxJS combAll Operator explained

I am trying to understand how the combine all operator works. I am using the following example from the official documentation :

import { take, map, combineAll } from 'rxjs/operators';
import { interval } from 'rxjs';

const source$ = interval(1000).pipe(take(2));

const example$ = source$.pipe(
  map(val =>
    interval(1000).pipe(
      map(i => 'Result (${val}): ${i}'),
      take(5)
    )
  )
);

example$
  .pipe(combineAll())
  .subscribe(console.log);


      

        
        
        
      

    

Then the output is:

["Result (0): 0", "Result (1): 0"]
["Result (0): 1", "Result (1): 0"]
["Result (0): 1", "Result (1): 1"]
["Result (0): 2", "Result (1): 1"]
["Result (0): 2", "Result (1): 2"]
["Result (0): 3", "Result (1): 2"]
["Result (0): 3", "Result (1): 3"]
["Result (0): 4", "Result (1): 3"]
["Result (0): 4", "Result (1): 4"]

      

        
        
        
      

    

Trying to understand why, I made this simple diagram:

I read from the documentation that every time any of the inner Observable emits a value, that emitted value is merged with the last value of all other inner Observables.

In the above diagram, we can see that the internal values ​​of the Observables emit 10 values ​​over time, so I expected to get an output with 10 values ​​over that time, but it is 9.

Also on the first line of the output:

["Result (0): 0", "Result (1): 0"]) 

      

        
        
        
      

    

Does 0 of Result (1): 0 correspond to null? Because the observed "inner 2" has not emitted anything yet?

To finish, here's what I expected as output:

["Result (0): 0", "Result (1): 0"]
["Result (0): 1", "Result (1): 0"]
["Result (0): 1", "Result (1): 0"]
["Result (0): 2", "Result (1): 0"]
["Result (0): 2", "Result (1): 1"]
["Result (0): 3", "Result (1): 1"]
["Result (0): 3", "Result (1): 2"]
["Result (0): 4", "Result (1): 2"]
["Result (0): 4", "Result (1): 3"]
["Result (0): 4", "Result (1): 4"]

      

        
        
        
      

    

This is clearly wrong, but I can't find my mistake, can someone please explain?