Let us take the case of forkJoin to understand Error Handling! Imagine having three input streams, out of which one fails while the other two succeed, what would happen? The forkJoin operation FAILS!

So a good idea here can be to not let forkJoin know if there was an error. And handle the errors of each of the input streams individually using catchError.

Finally subscribe to these in forkJoin.subscribe(next=> {})

https://betterprogramming.pub/rxjs-error-handling-with-forkjoin-3d4027df70fc