Is it true that you can't use a noun as a past participle adjective in #English?

Like it is:
* It's a low-risk situation.
* It's a high-risk investment.

But for some reason saying:
> It's a bad-faith argument.
Instead of:
> It's a bad-faithed argument.

Sounds wrong. I don't know why. To native speakers, which one of these two would you use and why? (Also mention if you're USA, UK, Australia, ... in case that makes a difference)

Also a side note for people in #silicon_valley that #program #spellcheckers stop assuming every language keeps the dash when combining words.
We don't do that here in Germany and because of that especially a lot of newer ones keep making incorrect suggestions. The hyphen is only kept for some words and some cases

Like in English it is "bus station" and when combined it would be "bus-station".
But in German it would be "Bushaltestelle" built out of the word for "bus" and "station" without hyphen

Here are all of the rules that apply for hyphen in German https://www.duden.de/sprachwissen/rechtschreibregeln/bindestrich

but sadly there is no English translation of them so that's probably why none of you appears to honnor them when programming spellcheckers these days.

A lot of spellcheckers in the early 2000s managed to provide the correct suggestions where their 2025 versions don't, that's just a quite disappointing regression as quite literally the code was already there...

Bindestrich

Der Bindestrich verbindet nicht nur, er trennt auch. Hier finden Sie kostenlos die wichtigsten Regeln für den richtigen Umgang mit ihm.

Duden

Also it would be great if #spellcheckers had a "consistent language" feature. Where when you enable multiple languages like English and German at the same time It knows that when you write "Babys" or "Partys" in an English sentence that it is wrong and should be "Babies" or "Parties".

But when one writes "Babies" or "Parties" in a German sentence that it is the other way around

Currently when both dictionaries are enabled it'll accept "Babies" in German and "Babys" in English sentences as well

Also before someone mentions #AI or #LLM in this context. Don't even bother.

Even the "AI" that duden I referenced above provides is making incorrect suggestions all of the time.

And if you want to be lazy, just pull out the code used in the early 2000s and ship that one instead...