It's because there are already other sounds that are represented by "sh", "j", and "u". For instance, the "sha" in Shanghai is pronounced differently from the "xia" in Xiamen, but that distinction doesn't really exist in English. Pinyin wasn't designed with only English speakers in mind, but also for use by Chinese people, who would be very confused by the standard English practice of assigning multiple pronunciations to the same letters or syllables. Rightfully so, as English spelling is a complete mess. That being said, I do think they went a little off the rails for iu (iou) and ui (uei), where dropping the middle letter makes it impossible to intuit.
Fair enough. If its for Chinese speakers, then I guess it makes sense. For English speakers, it is not very useful unless you were to spend a lot of time studying it.
You actively have to fight against how words "should" sound.
That's how other languages work... Nobody speaks other languages or names their cities just so that English speakers or Americans can know how to pronounce it... i mean we can say the same thing about French, who has a million letters in words that are somehow all silent. It's not designed for you to pronounce or spell or whatever. A very American take indeed, but after being on your site for 12 years, I don't expect anything less.
I always just type ngzhou and put whatever letter is needed at the beginning, trying different vowels, and if that doesn't work, then eliminate the "g" and try again. I first tried zangzhous and then zengzhou and I got credit for that one. Gungzhou, Hangzhou, Tengzhou, Wengzhou, Changzhou, Yangzhou, Wenzhou, Quanzhou, Lanzhou, etc.
Maybe because those just aren't correct lmao I guess you could argue Guangzu as just a horrendous misspelling of Guangzhou, however, you clearly confused Fukuoka with Fukushima (or maybe Iwo Jima? or both lmao) which is on the complete other side of the country. That's just not correct. I know the questions/answers to these quizzes change so maybe the answer used to be Fukushima but in that case you still just mashed Fukushima together with Iwo Jima which again just isn't correct. That's not a misspelling.
I'm always fascinated by "Ho Chi Minh City" as a quiz answer as NO ONE in the southern part of Vietnam, let alone in the city itself, calls it anything other than Saigon. You can't even find a tee shirt which references Ho Chi Minh City.
I kinda overthought some answers here - like actually sounding out the Thai script (Krung Thep Maha Nakhon) instead of just guessing the obvious B city in that country and then weirdly coming up with Okayama before Osaka as a Japanese city with O.
Or Zhengzhou. The first syllable sounds like "Jung" and the second syllable sounds like "Joe".
If they just spelled it Jungjoe, then English speakers could get kinda close. But instead Zhengzhou and there's literally zero chance.
You actively have to fight against how words "should" sound.