I think there's something about sounds that you learn early on in language acquisition - maybe your brain develops differently. 'th' is the obvious one that no

I think there's something about sounds that you learn early on in language acquisition - maybe your brain develops differently. 'th' is the obvious one that non-english speakers struggle with. I remember a dutch guy laughing at my attempts at various dutch words - I literally could not hear the difference between his pronunciation and mine. And 'ch' (as in Loch or Bach) is a sound in Scottish english but not in English english. I lived in Scotland till I was 4, then moved to England and all traces of my previous Scottish accent are long long gone. But my friend, whose surname is Donnachie, says I'm the only English person she's met who pronounces her name correctly - I guess because I learnt that sound early on. Similarly, my dad, who learnt english in India, still struggles with a "j" sound (he says "zudge" instead of "judge"), despite living here for 50 years and having a posh middle-class English accent that sounds just like a "native" english speaker.