Why are the subtitles so bad?

When I watch Netflix in English with German subtitles, I realize how badly some things are translated:

For example, "Stay in your league" is translated as "Stay with your last".

Do you get a job at Netflix as an amateur?

Exactly the same, I suspect too. Either the translators are drunk or it is automatically translated by bot. For most films / series you can see who the subtitles are.
I have nothing against it when the sentences are changed a bit, so that they make more sense in German, but then please correct.
But often not only is the wording poor or inappropriate, but sometimes even spelling mistakes are involved and often just parts of a sentence are not translated at all. I notice this especially in series where Spanish is spoken. Just cruel partly.

The subtitles should not be a 1: 1 translation, but make sense in context. "Stay with your last" is in the case a saying that one applies if someone interferes somewhere, of which he has no idea.
Without knowing the context, it certainly makes more sense than anything else.

Because usually everything is translated one to one without thinking too much about it. Or simply iwie so that it fits halfway

"Stay in your league" would be perfectly appropriate. Personally, I have never used or heard the above saying.

In your example, the translation is true, so no cause for excitement.

https://www.geo.de/geolino/redewendungen/13380-rtkl-redewendung-schuster-bleib-bei-deinem-leisten

https://de.wiktionary.org/wiki/Schuster,_bleib_bei_deinem_Leisten

Then your German vocabulary is probably not very pronounced. "Cobbler, stay with your last!" is an absolutely common, enormously widespread saying in German. "Stay in your league!" would be extremely awkward and too literally translated. But hey, about such literal translations have already crept into expressions such as "Have a good time" in German * shudder * …

"… And often just parts of a sentence are not translated at all."

Since people talk faster than they read, it is often inevitable.

Or that does not make sense That makes no sense.

Are we in Latin class, that it must be a 1: 1 implementation? As long as it means the same thing, that's no problem.

Otherwise, it is fine, a somewhat unusual translation but still fitting.

https://de.wiktionary.org/wiki/Schuster,_bleib_bei_deinem_Leisten

This is correct, even when subtitles are in the same language as the dialogue it is translated so poorly, it's actually pretty serious and should cause a concern. A big corporation such as Netflix doesn't care for proper language. It's shows the dumbing down of humans really. And our "liberal" concerns.