What would be a real world usage or need of the Rx operator Never?

Question

Why would you ever subscribe to or even create an observable that never yields anything, not even an error, nor completion?

Answer 1

It is a fundamental "atom" in the composition of observable event streams and comes up in a variety of situations - but one of the most common uses for Observable.Never in practice is in writing tests. It easily enables robust checking of timeout logic, for example - and is often combined with the TestScheduler or other virtual time schedulers in test scenarios. If you examine the source code of Rx itself, you find it appears in many unit tests.