I think this is the salient point. And satisfies hx9’s point about having it both ways.
Years ago I was dating a Colombian girl, and my Spanish skills were only mediocre. I was at her place for the first time, and we were cooking. I didn’t know the word for butter, so I described it (in Spanish, using words I’ve lost even more of by now) as “the thing from cows that you spread on toast”. She knew what I meant, but her English wasn’t quite good enough to tell me the butter was almost gone, so she handed me the tiny amount that was left and said “it’s gonna over”.
We both knew exactly what the other meant, and to this day I still think “it’s gonna over” when I see some resource is running low. 
I know that all the people who tell me “watch out, there’s not a perfect mapping between English and Japanese” are correct. But I also get just a little bit of a rebellious urge to push back, because… c’mon. Language is for communication, and we know that bilingual people in these cultures are perfectly able to communicate. My Japanese partner has been using English as her “primary” daily language for over 15 years (the second half of her life), and she’s very good, but it’s still obvious it’s a second language. Phonetically, she still struggles with l’s and r’s (as I always will in her language… I make her judge my 便利 pronunciation daily), and semantically she very often leaves out prepositions and articles (“I’m going gym” is a frequent text I get from her), and gendered pronouns still trip her up (any time she uses one, she usually says “he… she” in rapid succession, like she didn’t know which to choose so just threw both out to be safe). But even with all of those tiny mistakes, she’s never once had an issue communicating with me. Nothing has ever been lost in translation between us. Though I’ll admit some archaic phrases that we hear in old American movies are hard for me to explain to her (but maybe because I don’t even fully grasp them myself).
And even though the engineer in me wants to approach this like a perfect mathematical system… that is only the ideal model, which I know is unattainable. But unattainable goals still have value, and that value here is to get me as close to friction-free communication as possible. 