One common mistake that we make while trying to improve our communication skills is solely focusing on improving vocabulary and grammar and tone, while not focusing much on the structure of how we speak/write.
I & many others I know from the first company that I worked in faced a similar problem. All of us were fresh out of college and had memorized words (mostly from vocabulary cards) for entrance exams like GRE, CAT, and GMAT. The emails that we wrote back then contained words like “bouts,” “nebulous,” “conspicuous,” and “esoteric”. There is nothing wrong with the words itself but the whole point of business communication is to inform the receiver in the most efficient way possible. Efficiency here means two things; time to understand the message should be as less as possible, and the message should be clear (no ambiguity). The choice of such words increased the time to understand the message (as some people would google those words to understand).
The important and yet less focussed part of business communication is how you structure your content. A good strategy is to use the pyramid principle i.e. start with the outcome/answer/conclusion. Then give the supporting arguments that led you to that conclusion, followed by the data/insight that led to that argument. Group argument/information at the same level together.
For eg: Previously: 90% of our customers do not use both channels of mobile and web, they stick to one channel. Thus we do not need to optimize for a cross-channel user experience.
Updated with pyramid: We do not need cross-channel user experience as 90% of our customers stick to one channel and do not migrate to the other channel.