How do words/names in other alphabets get (mis)translated into ours?

There are lots of doubled or geminated consonant sounds in English and in some cases the difference between the geminated and nongeminated version distinguishes different words (or phrases). There is a short list in the Wikipedia article, including “midday”, “lamppost”, and “roommate”. An example of two words, identical except for gemination, is “unaimed” vs. “unnamed”.

Except this requires that the Latin alphabet to transparently render English phonemes to an English speaking reader, and this can never happen.

What sound does “th” represent? “Thin”, “this” and “goatherd” have the same collection of letters, but they represent different sounds. There is no one to one correlation of English phonemes to Latin characters. For foreign words in a language that uses the Latin alphabet we can just use whatever spelling they use.

Oh, so we should stop using the name “Rome” and instead use “Roma”? Instead of saying “Germany” we should write “Deutschland”? The problem here is that the English word for the country is Germany, despite the fact that the people in Germany don’t call it Germany.

And it’s doubly confusing for countries that don’t use the Latin alphabet. However, there’s one advantage. Remember how there’s consistent system of transcribing English words using the Latin alphabet? That’s because English spelling evolved haphazardly over hundreds of years. However with foreign languages we don’t have to use that haphazard system, we can invent a transcription system. And so in Pinyin an unaspirated “p” sound is transcribed using the character “b” and an aspirated “p” sound is transcribed using the character “p”.

And so how do we transcribe the name of the capital of China using the Pinyin system? And the answer is “Beijing” If you know how the Pinyin system works, you can know how the name of that city is pronounced in Mandarin. However, the problem with Pinyin is that it uses certain Latin characters differently than English. So how is the name “Xi’an” pronounced? If you know how Pinyin works that’s easy, the “x” character represents a sound that is usually represented by “sh” in English. Except “sh” doesn’t represent that sound in other languages that use the Latin alphabet, only in English.

Yes, in English works we could transliterate the name as “Shian”. Except now we’ve got a custom transliteration system for Chinese, rather than a consistent one. If we stick with Pinyin at least we know what we’re doing, even if we sometimes make mistakes all we need to do is learn Pinyin and we know what we’re talking about.

This. I don’t understand people who think it’s possible to spell “phonetically” in English.

Here’s an interesting example – “Beijing”. This (pinyin) spelling is already about as close as you can get to spelling it phonetically in English. Yet I constantly hear English speakers pronounce the “j” as /ʒ/; that is, like the “s” in “pleasure”. In reality the Chinese phoneme is pretty close to the “j” in English “jeep”. I’m not sure why so many people choose a rare pronunciation of the “j” rather than the more common one, unless it’s just a subconscious feeling that a foreign word should use an unusual phoneme.

I’m no expert on Korean, but when I went to the country in 1981 I had to contend with the pronunciation of the place names at least. It seems that Korean has a sort of aspirated ‘b’ that is not voiced as strongly as an English ‘p’, in other words, it is between the two. I suspect that there is a similar problem in Arabic, as Arabic speakers also have a problem distinguishing
p and b.
To reiterate a point ad nauseam, the Latin alphabet does not do a good job of transliterating languages, even European ones, and even those generally need some help with accents.