Nathan
Your question is entirely reasonable.
Aside from the specific terminology used in your work/occupation/profession, the manner in which we communicate and the style of writing and speaking is dependent on the situation and the people we are addressing.
One major distinction between casual work-related conversation and critical time-sensitive communication is dependent on the speaker's ability to get to the point. After all, in business, time is money.
And, a qualified business language teacher, who has extensive business experience, can provide insight into how different nationalities do business, i.e., business culture.
BTW, almost every university offers Business English Courses online or in-situ.
If business English courses did not exist, then someone should inform Oxford, Cambridge, and Harvard.