This Multi-purpose Brew Stick can be used to agitate grounds during the brew process for better tasting coffee or work as a long-form stir stick. What is Agitation? Agitation (sometimes referred to as turbulence) is the process of mixing or shuffling coffee grounds while brewing. Why should I do this? When you agitate your coffee grounds, you ensure water passes through your coffee in a more uniform fashion, resulting in a better tasting coffee!