
Always.
Fun principle behind this: you can recognize sounds very easily, but it’s much harder to reproduce them. Think of all the sounds you know the meanings of: car alarms, the music introductions to programs, etc. You can identify them and what they mean very quickly. However, learning to make those sounds is much harder. The basic reason (and this is very basic) is that your ears are designed to pick up different sounds, so it’s only the audio part of your brain that has to learn what each means. By contrast, to make a sound face, tongue, vocal, and memory all have to work together.