Variance in anime subtitles & the art of translation

So I am still at the stage of watching Japanese dramas and anime with English subtitles; I shouldn't be at this point, but I spent far too long learning via the green bird, and am still trying to make up ground. But I am at the point where I can pick out words in sentences, or completely understand simple sentences.

Whilst I know that the subtitles are never a direct literal translation of whats being said, and translators might decide to inject some character personality into a translation; I have begun to notice that sometimes the same word can be translated multiple ways, even within the same episode.

I'm trying to remember exactly where I saw it now, but the example that keeps coming into my mind is:

『わかりました』

Which was subtitled as; "Got it" & "Understood", in the same episode.

Now I know that this is still an accurate meaning/translation, but how do subtitle makers decide how to translate something one way vs another?

And when I progress enough to move away from using English subtitles, is there a specific way (such as tone), that I am meant to be able to understand which way to translate it? Or is understanding the meaning of the word enough?

by foster1984