Final answer:
Diane's omission of negative feedback in an end-of-year summary report represents a barrier to effective communication known as 'Deceptive tactics', which involves knowingly misrepresenting information.
Step-by-step explanation:
When drafting an end-of-year summary report, Diane's omission of negative feedback likely represents a barrier of effective communication known as Deceptive tactics. This term reflects a conscious choice to misrepresent information, often in a way that could make the situation appear more favorable than it is. This is akin to what happens when individuals respond to surveys by altering their answers to be seen in a better light or due to social desirability bias.
In communication, it's essential to acknowledge and address all relevant feedback, both positive and negative, to ensure a comprehensive and honest evaluation of the situation. Failure to do so can prevent a clear understanding and hinder constructive progress, as stakeholders are not fully informed about potential issues or areas in need of improvement.