What are some commonly accepted ways in which audience position in the buying cycle changes digital advertising / paid search choices in respect of the customer benefit of search?

What are some commonly accepted ways in which audience position in the buying cycle changes digital advertising / paid search choices in respect of the customer benefit of search? Answers must include: Definition of terminology, Importance of the concept or process, and the Process of how a professional marketer approaches the practice. Please start your answer so it can stand alone as a sentence/paragraph. For example, “SEO keyword analysis is the process of…”