A rhetorical [[refutatio]] isn't just a "counterargument." It might also be an ambiguity, complication or concession. This is why it makes sense for a refutatio to come towards the end of a speech, since [[the end of a speech is oriented towards the future]]. First you establish what we already know (the past), then you add your research, and then you address what we still don't know or what's ambiguous. The refutatio is the bridge between your research and your call to further research.