In simple terms, juggling is about throwing and catching at the same time. And therein lies the challenge. Throwing is easy. Catching is easy. So why is juggling hard? Because you have to learn a new skill which is to concentrate on two actions at the same time without giving too much weight to either – because if you do, you can’t give sufficient weight to the other action and the process fails. Either action can be the point of failure. Pay too much attention to catching and you don’t throw well. Pay too much attention to throwing well and you won’t catch the ball.
Listening to a foreign language reminds me of juggling. When listening to someone speak, you have to hear a sound and interpret the meaning (action 1. translation) whilst listening to and storing the next sound (action 2. listening). If you find the meaning of a word or group of words becomes too important then you will concentrate. Concentration is, by definition, a process of exclusion, so you won’t have enough attention left to listen to the next words coming in.
As a child you were used to hearing lots of words you didn’t know. You just let the ones you didn’t know go and allowed the words you did know to coalesce into meaning. But as an adult you are used to understanding pretty much every word you hear in your native language, which can create the bad habit of wanting to understand every word you hear in a foreign language. And while you are struggling to find the meaning of one word or group of words, you have insufficient bandwidth to hear the next group arriving.
That’s one reason reading is easier than listening for most people. Because they can pause their reading while they search for meaning.
So if you want to improve your listening skills, think of it like juggling. Don’t allow yourself to become too focussed on any single aspect of the activity. Try but don’t try too hard. Allow meaning to occur rather than trying to make meaning occur.