Yes, the Chinese are often surprised. It seems that they can create good things, but every time there is some error in them. They have science and high technology, but they don't achieve quality.
I have a Rigol MSO5074-a good device, a complex development, but why they did not put load resistors on the LVDS receiver side of the logic analyzer is not clear.
And at the KSGER thermofen so in general the wires are connected incorrectly.
Probably, rapid progress does not provide a reliable Foundation, which is developed by long experience.
Don't get it wrong. Chinese are like all other countries, you get what you pay for.
Buying a $30 soldering station, that includes aluminium casing, oled screen, handle, iron tips... Don't expect a miracle!
The fact that it works is already surprising

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There're different target markets. The high quality, expensive ones... and the aliexpress market.
Tons of cheap stuff, but don't compare them to what you usually would buy for 500% it's price.
Since Aliexpress targets that market, the engineers try to low the cost to the minimum.
When comparing options, let's say you find a soldering station for $28 and another for $30.
From the average user, maybe the ~70% just want to play with arduino and such, but aren't electronics themselves, so will buy the cheapest.
So the numbers make the rules. More quality for $5 more? Or $5 less and sell a lot more that the rivals?
People like us might do a more in-depth research trying to identify the working parts and difference the good vs the crap ones.
Unless they make pictures of the internals, who knows? Nowadays they also do that trick, rise the price $10 to look like it's much better, then you receive the same crap.
So that's the problem. It's not easy to buy with confidence.
But in the quality market, you can get a Jabe UD-1200 clone for $180, half the JBC price, includimg some iron tips (JBCs will costs $30+ each one).
But a you see, the price is not in the same league!
I must admit that they could do much better with some research. Maybe spending $2 more they could fix a lot of things.
But, just looking at the firmware... They don't even use the hardware peripherals. They drive the SPI devices by software and such things.
That means, they don't want to lose any time in development. Take already made code that works (and will work on any device because it's software), and build the firmware with copy & paste.
That leads to what we often see... horrendous performance from a relative powerful MCU, with a screen that have tearing lines and 5HZ refresh rate, laggy controls...