Business Analyst Principle: Understand how your stakeholders learn.
The key to effective communication is understanding how the other person learns. Once you understand how they learn you can communicate your message in a manner that they will understand.
Your job as a business analyst ends when you know they have understood your message. Not only do you have to state your message, but you also need to ask follow-up questions such that both parties know they understand.
There are four main modalities for learning: kinesthetic, visual, auditory, and tactile. Kinesthetic learners typically learn through doing, auditory through hearing, visual through seeing, and tactile through touching. All stakeholders have varying degrees of each.
With these four modalities, the process of communication becomes complicated. If we assume a person can only have 10 varying degrees of each modality, the combination of all four means that there would be 10,000 different types of stakeholders. (10x10x10x10)
There are other factors that affect communication as well. Some stakeholders need to have a personal connection to be willing to accept new ideas. Other stakeholders may require trust that you understand the domain to accept new ideas.
In the end, as a business analyst, you need to be willing to try different ways to both get your message across as well as to confirm that the stakeholder understands. In the real world, this is a two-way street. There are very few, I would say none, situations where you as the business analyst know the entire answer. You know part of the answer and the stakeholder knows part of the answer. You need to learn from the stakeholder, and they need to learn from you.
Be sure to create an open environment for sharing and learning from each other.