1. You don't, as said before. 2. Creating dispatch queues is trivial and most surely you already created one for other tasks. 3. You miss the context of this

1. You don't, as said before. 2. Creating dispatch queues is trivial and most surely you already created one for other tasks. 3. You miss the context of this article. Try doing that on the main thread of a simple command line utility and nothing happens. Try locking the main thread of a GUI Application, and you did a beginners mistake, your App will lock. GUI API calls must be done on the main thread and that's where our View Controllers run in.