https://twitter.com/inamiy/status/1254308875487989760

combine-delay-without-cancellable.swift

Just(())
    .delay(for: 1, scheduler: DispatchQueue.main)
    .sink {
        print("Q1. Can you hear me?") // Yes, even without retaining cancellable. Do you know why? :)
    }

Just(())
    .delay(for: 1, scheduler: DispatchQueue.main)
    .flatMap { Just(()) }
    .sink {
        print("Q2. Can you hear me?") // No, because of not retaining cancellable
    }