I do recall reading that it's impossible to learn how to make certain sounds if you haven't learned them in childhood. I don't think I believe that it's actual

I do recall reading that it's impossible to learn how to make certain sounds if you haven't learned them in childhood. I don't think I believe that it's actually impossible though, at least not for everyone. What seems more likely to me is that for most people it's just not necessary or practical to become 'accentless', or at least it's not perceived to be worth the effort or money (for a vocal coach, or something like that). A child not only has a brain that is (probably) optimized at that point in time to learn languages, but a child also has the privilege of being immersed in the language to learn, as well as massive amounts of free time to do so. Not to mention a lack of shame of messing up (or judgment for doing so).