If you haven’t heard a spoken sound in your first few years of life (I’ve even seen people claim months), it’s very hard to learn to tell the difference well. You can learn to pronounce them perfectly at any age, but a lot of the time subtly different words will be hard to distinguish if you didn’t grow up with hearing them.
Argentinians (and possibly other Spanish speakers) struggle with e.g. “peach” vs “pitch”, and worry about mispronouncing “beach”.
Some Asians famously struggle with R vs L, which seems baffling to a speaker of western languages, but if you actually look at the frequencies, they’re nearly identical sounds. We’ve just been trained from infancy to hone in on the difference to the point that it’s hard to comprehend them sounding similar to other people.








Sounds overkill. They were allegedly 00000000 from 1962 to 1977, and we turned out fine!