Thank you Craig for your feedback! You are absolutely right that in the case of remote REST API calls, the observable will complete once the API has returned a result or failed, and subscriptions will be automatically unsubscribed and eventually garbage collected.

However, I would like to mention that the example provided in the article was intended to showcase the usage of observables in Angular in general and was not limited to remote API calls. It is true that the scenario where the observable completes after a single emission is not the most common use case, but there are other situations where observables may continue to emit values indefinitely, such as real-time updates, and in these cases, it's important to properly unsubscribe to avoid memory leaks.

That being said, I appreciate your feedback and will add a disclaimer to the article to clarify this point. Thank you again for taking the time to read and comment on my article!